Large impacts of small methane fluxes on carbon isotope values of soil respiration

Carbon dioxide isotope (δ13C of CO2) analysis is increasingly used to address a broad range of questions involving soil C dynamics and respiration sources. However, attaining δ13C mass balance is critical for robust interpretation. Many ecosystems exhibit methane (CH4) fluxes that are small in the context of total C budgets, yet may significantly impact δ13C values of CO2 due to large kinetic fractionations during CH4 production. Thus, the δ13C values of CO2 do not directly reflect respiration C sources when co-occurring with CH4, but few studies of terrestrial soils have considered this phenomenon. To assess how CH4 altered the interpretation of δ13C values of CO2, we incubated a Mollisol and Oxisol amended with C4-derived plant litter for 90 days under two headspace treatments: a fluctuating anaerobic/aerobic treatment (four days of anaerobic conditions alternating with four days of aerobic conditions), and a static aerobic treatment (control). We measured δ13C values of CO2 and CH4 with a tunable diode laser absorption spectrometer, using a novel in-line combustion method for CH4. Cumulative δ13C of CO2 differed significantly between treatments in both soils. The δ13C values of CO2 were affected by relatively small CH4 fluxes in the fluctuating anaerobic/aerobic treatment. Effects of CH4 on δ13C values of CO2 were greater in the Oxisol due to its higher percent contribution of CH4 to total C mineralization(18%) than in the Mollisol (3%) during periods of elevated CH4 production. When CH4accounted for just 2% of total C mineralization, the δ13C values of CO2 differed from total C mineralization by 0.3–1‰, and by 1.4–4.8‰ when CH4 was 10% of C mineralization. These differences are highly significant when interpreting natural abundance δ13C data. Small CH4fluxes may strongly alter the δ13C values of CO2 relative to total mineralized C. A broad range of mineral and peatland soils can experience temporary oxygen deficits. In these dynamic redox environments, the δ13C values of CO2 should be interpreted with caution and ideally combined with δ13C of CH4 when partitioning sources and mechanisms of soil respiration

Patterns and outcomes of subsequent therapy after immune checkpoint inhibitor discontinuation in HCC

The availability of immune checkpoint inhibitors (ICIs) for the management of advanced hepatocellular cancer (HCC) has changed the treatment paradigm. There are emerging questions regarding the efficacy of subsequent anticancer therapies. The primary aim of this retrospective, multicenter study was to examine the types of anticancer treatment received after ICIs and to assess the impact on post-ICI survival. We established an international consortium of 11 tertiary-care referral centers located in the USA (n = 249), Europe (n = 74), and Asia (n = 97), and described patterns of care following ICI therapy. The impact of subsequent therapy on overall survival (OS) was estimated using the Kaplan–Meier method and presented with a 95% confidence interval (CI). A total of 420 patients were treated with ICIs for advanced HCC after one line of systemic therapy (n = 371, 88.8%): 31 (8.8%) had died, 152 (36.2%) received best supportive care (BSC) following ICIs, and 163 patients (38.8%) received subsequent anticancer therapy. Tyrosine kinase inhibitors (TKIs, n = 132, 80.9%), in particular sorafenib (n = 49, 30.0%), were the most common post-ICI therapy followed by external beam radiotherapy (n = 28, 17.2%), further immunotherapy (n = 21, 12.9%), locoregional therapy (n = 23, 14.1%), chemotherapy (n = 9, 5.5%), and surgery (n = 6, 3.6%). Receipt of post-ICI therapy was associated with longer median OS compared with those who had received BSC (12.1 vs. 3.3 months; hazard ratio [HR]: 0.4 (95% CI: 2.7–5.0). No difference in OS was noted in those patients who received TKI before ICIs compared with those who received ICIs followed by TKI. Conclusion: Post-ICI therapy is associated with OS in excess of 12 months, suggesting a role for therapeutic sequencing. OS from TKI therapy was similar to that reported in registration studies, suggesting preserved efficacy following ICIs

Impact of older age in patients receiving atezolizumab and bevacizumab for hepatocellular carcinoma

Background and Aims Combination atezolizumab/bevacizumab is the gold standard for first-line treatment of unresectable hepatocellular carcinoma (HCC). Our study investigated the efficacy and safety of combination therapy in older patients with HCC. Methods 191 consecutive patients from eight centres receiving atezolizumab and bevacizumab were included. Overall survival (OS), progression-free survival (PFS), overall response rate (ORR) and disease control rate (DCR) defined by RECIST v1.1 were measured in older (age ≥ 65 years) and younger (age < 65 years) age patients. Treatment-related adverse events (trAEs) were evaluated. Results The elderly (n = 116) had higher rates of non-alcoholic fatty liver disease (19.8% vs. 2.7%; p < .001), presenting with smaller tumours (6.2 cm vs 7.9 cm, p = .02) with less portal vein thrombosis (31.9 vs. 54.7%, p = .002), with fewer patients presenting with BCLC-C stage disease (50.9 vs. 74.3%, p = .002). There was no significant difference in OS (median 14.9 vs. 15.1 months; HR 1.15, 95% CI 0.65–2.02 p = .63) and PFS (median 7.1 vs. 5.5 months; HR 1.11, 95% CI 0.54–1.92; p = .72) between older age and younger age. Older patients had similar ORR (27.6% vs. 20.0%; p = .27) and DCR (77.5% vs. 66.1%; p = .11) compared to younger patients. Atezolizumab-related (40.5% vs. 48.0%; p = .31) and bevacizumab-related (44.8% vs. 41.3%; p = .63) trAEs were comparable between groups. Rates of grade ≥3 trAEs and toxicity-related treatment discontinuation were similar between older and younger age patients. Patients 75 years and older had similar survival and safety outcomes compared to younger patients. Conclusions Atezolizumab and bevacizumab therapy is associated with comparable efficacy and tolerability in older age patients with unresectable HCC

Relevance of laboratory testing for the diagnosis of primary immunodeficiencies: a review of case-based examples of selected immunodeficiencies

The field of primary immunodeficiencies (PIDs) is one of several in the area of clinical immunology that has not been static, but rather has shown exponential growth due to enhanced physician, scientist and patient education and awareness, leading to identification of new diseases, new molecular diagnoses of existing clinical phenotypes, broadening of the spectrum of clinical and phenotypic presentations associated with a single or related gene defects, increased bioinformatics resources, and utilization of advanced diagnostic technology and methodology for disease diagnosis and management resulting in improved outcomes and survival. There are currently over 200 PIDs with at least 170 associated genetic defects identified, with several of these being reported in recent years. The enormous clinical and immunological heterogeneity in the PIDs makes diagnosis challenging, but there is no doubt that early and accurate diagnosis facilitates prompt intervention leading to decreased morbidity and mortality. Diagnosis of PIDs often requires correlation of data obtained from clinical and radiological findings with laboratory immunological analyses and genetic testing. The field of laboratory diagnostic immunology is also rapidly burgeoning, both in terms of novel technologies and applications, and knowledge of human immunology. Over the years, the classification of PIDs has been primarily based on the immunological defect(s) ("immunophenotype") with the relatively recent addition of genotype, though there are clinical classifications as well. There can be substantial overlap in terms of the broad immunophenotype and clinical features between PIDs, and therefore, it is relevant to refine, at a cellular and molecular level, unique immunological defects that allow for a specific and accurate diagnosis. The diagnostic testing armamentarium for PID includes flow cytometry - phenotyping and functional, cellular and molecular assays, protein analysis, and mutation identification by gene sequencing. The complexity and diversity of the laboratory diagnosis of PIDs necessitates many of the above-mentioned tests being performed in highly specialized reference laboratories. Despite these restrictions, there remains an urgent need for improved standardization and optimization of phenotypic and functional flow cytometry and protein-specific assays. A key component in the interpretation of immunological assays is the comparison of patient data to that obtained in a statistically-robust manner from age and gender-matched healthy donors. This review highlights a few of the laboratory assays available for the diagnostic work-up of broad categories of PIDs, based on immunophenotyping, followed by examples of disease-specific testing

Perspectives on the neoadjuvant use of immunotherapy in hepatocellular carcinoma

Immune checkpoint inhibitor (ICI) therapy is an increasingly used treatment modality across the various stages of hepatocellular cancer (HCC). There is currently no standard peri-operative therapy for HCC, despite a high probability of recurrence. Emerging studies in a variety of tumors demonstrate significant pathologic and immune responses to neoadjuvant immunotherapy. Unlike kinase inhibitors and other targeted therapies, which demonstrated no benefit in the adjuvant setting and fail to induce significant responses, ICIs can induce radiologically appreciable reduction in disease burden, which make ICI combinations an appealing downstaging strategy in patients early or locally advanced disease. Additionally, induction of anti-tumor immunity in the pre-operative setting may induce protracted T-cell response that, in the post-operative phase, may be capable of eliminating micro-metastatic disease and prevent future recurrence. In this review, we discuss the rationale and clinical hurdles that underlie optimal integration of immunotherapy in the pre-operative setting, highlighting the positive impact on surgical and oncological outcomes in patients with early-stage HCC

Non-Euclidean classification of medically imaged objects via s-reps

Classifying medically imaged objects, e.g., into diseased and normal classes, has been one of the important goals in medical imaging. We propose a novel classification scheme that uses a skeletal representation to provide rich non-Euclidean geometric object properties. Our statistical method combines distance weighted discrimination (DWD) with a carefully chosen Euclideanization which takes full advantage of the geometry of the manifold on which these non-Euclidean geometric object properties (GOPs) live. Our method is evaluated via the task of classifying 3D hippocampi between schizophrenics and healthy controls. We address three central questions. 1) Does adding shape features increase discriminative power over the more standard classification based only on global volume? 2) If so, does our skeletal representation provide greater discriminative power than a conventional boundary point distribution model (PDM)? 3) Especially, is Euclideanization of non-Euclidean shape properties important in achieving high discriminative power? Measuring the capability of a method in terms of area under the receiver operator characteristic (ROC) curve, we show that our proposed method achieves strongly better classification than both the classification method based on global volume alone and the s-rep-based classification method without proper Euclideanization of non-Euclidean GOPs. We show classification using Euclideanized s-reps is also superior to classification using PDMs, whether the PDMs are first Euclideanized or not. We also show improved performance with Euclideanized boundary PDMs over non-linear boundary PDMs. This demonstrates the benefit that proper Euclideanization of non-Euclidean GOPs brings not only to s-rep-based classification but also to PDM-based classification

Name Institution email

FU Berlin) organisiert. 35 Teilnehmer aus Universitäten und Industrie waren angemeldet; es fanden 12 Präsentationen und die Vorführung einiger Demonstratoren statt. Dieser Bericht enthält die Beschreibungen dieser Präsentationen sowie einige der vorgestellten Foliensätze. Die Organisatoren hoffen, daß diese Veranstaltung die Zusammenarbeit und Qualität der Forschung zu Sensornetze