Immunoglobulin G-dependent inhibition of inflammatory bone remodeling requires pattern recognition receptor Dectin-1.

Immunoglobulin G (IgG) antibodies are major drivers of inflammation during infectious and autoimmune diseases. In pooled serum IgG (IVIg), however, antibodies have a potent immunomodulatory and anti-inflammatory activity, but how this is mediated is unclear. We studied IgG-dependent initiation of resolution of inflammation in cytokine- and autoantibody-driven models of rheumatoid arthritis and found IVIg sialylation inhibited joint inflammation, whereas inhibition of osteoclastogenesis was sialic acid independent. Instead, IVIg-dependent inhibition of osteoclastogenesis was abrogated in mice lacking receptors Dectin-1 or FcγRIIb. Atomistic molecular dynamics simulations and super-resolution microscopy revealed that Dectin-1 promoted FcγRIIb membrane conformations that allowed productive IgG binding and enhanced interactions with mouse and human IgG subclasses. IVIg reprogrammed monocytes via FcγRIIb-dependent signaling that required Dectin-1. Our data identify a pathogen-independent function of Dectin-1 as a co-inhibitory checkpoint for IgG-dependent inhibition of mouse and human osteoclastogenesis. These findings may have implications for therapeutic targeting of autoantibody and cytokine-driven inflammation.

T-bet suppresses proliferation of malignant B cells in chronic lymphocytic leukemia.

The T-box transcription factor T-bet is known as a master regulator of T-cell response but its role in malignant B cells is not sufficiently explored. Here, we conducted single-cell resolved multi-omics analyses of malignant B cells from patients with chronic lymphocytic leukemia (CLL) and studied a CLL mouse model with genetic knockout of TBX21. We found that T-bet acts as a tumor suppressor in malignant B cells by decreasing their proliferation rate. NF-κB activity induced by inflammatory signals provided by the microenvironment, triggered T-bet expression which impacted on promoter proximal and distal chromatin co-accessibility and controlled a specific gene signature by mainly suppressing transcription. Gene set enrichment analysis identified a positive regulation of interferon signaling, and a negative control of proliferation by T-bet. In line, we showed that T-bet represses cell cycling and is associated with longer overall survival of CLL patients. Our study uncovers a novel tumor suppressive role of T-bet in malignant B cells via its regulation of inflammatory processes and cell cycling which has implications for stratification and therapy of CLL patients. Linking T-bet activity to inflammation explains the good prognostic role of genetic alterations in inflammatory signaling pathways in CLL.

RIM and RIM-binding protein localize synaptic CaV2 channels to differentially regulate transmission in neuronal circuits.

At chemical synapses, voltage-gated Ca2+-channels (VGCCs) translate electrical signals into a trigger for synaptic vesicle (SV) fusion. VGCCs and the Ca2+ microdomains they elicit must be located precisely to primed SVs, to evoke rapid transmitter release. Localization is mediated by Rab3 interacting molecule (RIM) and RIM-binding proteins (RIM-BPs), which interact and bind to the C-terminus of the CaV2 VGCC α-subunit. We studied this machinery at the mixed cholinergic/GABAergic neuromuscular junction (NMJ) of Caenorhabditis elegans hermaphrodites. rimb-1 mutants had mild synaptic defects, through loosening the anchoring of UNC-2/CaV2 and delaying the onset of SV fusion. UNC-10/RIM deletion much more severely affected transmission. Even though postsynaptic depolarization was reduced, rimb-1 mutants had increased cholinergic (but reduced GABAergic) transmission, to compensate for the delayed release. This did not occur when the excitation-inhibition balance was altered by removing GABA transmission. Further analyses of GABA defective mutants and GABAA or GABAB receptor deletions, as well as cholinergic rescue of RIMB-1, emphasized that GABA neurons may be more affected than cholinergic neurons. Thus RIMB-1 function differentially affects excitation/inhibition balance in the different motor neurons, and RIMB-1 thus may differentially regulate transmission in mixed circuits. Untethering the UNC-2/CaV2 channel by removing its C-terminal PDZ ligand exacerbated the rimb-1 defects, and similar phenotypes resulted from acute degradation of the CaV2 ß-subunit CCB-1. Therefore, untethering of the CaV2 complex is as severe as its elimination, yet does not abolish transmission, likely due to compensation by CaV1. Thus, robustness and flexibility of synaptic transmission emerges from VGCC regulation.Significance statement The machinery for chemical synaptic transmission is organized in a precise spatial arrangement in order to enable efficient and temporally accurate coupling of action potentials with the rise of the Ca2+ concentration through CaV2 P/Q-type voltage gated Ca2+ channels. This triggers the fusion of synaptic vesicles with the plasma membrane and the release of transmitters. Here, we analyzed the molecular and functional interplay of proteins of the active zone scaffold, RIM and RIM-binding protein (RIMB-1), with the CaV2 channel in the C. elegans neuromuscular junction, a tripartite synapse with cholinergic and GABAergic neuronal input. Our work shows a differential requirement of RIMB-1 in cholinergic vs. GABAergic neurons, that affects the regulation of excitation-inhibition balance at circuit, cellular and ultrastructural levels.

Competition for cysteine acylation by C16:0 and C18:0 derived lipids is a global phenomenon in the proteome.

S-acylation is a reversible posttranslational protein modification consisting of attachment of a fatty acid to a cysteine via a thioester bond. Research over the last few years has shown that a variety of different fatty acids, such as palmitic acid (C16:0), stearate (C18:0), or oleate (C18:1), are used in cells to S-acylate proteins. We recently showed that GNAI proteins can be acylated on a single residue, Cys3, with either C16:0 or C18:1, and that the relative proportion of acylation with these fatty acids depends on the level of the respective fatty acid in the cell's environment. This has functional consequences for GNAI proteins, with the identity of the acylating fatty acid affecting the subcellular localization of GNAIs. Unclear is whether this competitive acylation is specific to GNAI proteins or a more general phenomenon in the proteome. We perform here a proteome screen to identify proteins acylated with different fatty acids. We identify 218 proteins acylated with C16:0 and 308 proteins acylated with C18-lipids, thereby uncovering novel targets of acylation. We find that most proteins that can be acylated by C16:0 can also be acylated with C18-fatty acids. For proteins with more than one acylation site, we find that this competitive acylation occurs on each individual cysteine residue. This raises the possibility that the function of many different proteins can be regulated by the lipid environment via differential S-acylation.

Distal Pancreatectomy: Extent of Resection Determines Surgical Risk Categories.

BACKGROUND: Recently, subclassification of pancreatoduodenectomy in 4 differing types has been reported, because additional major vascular and multivisceral resections have been shown to be associated with an increased risk of postoperative morbidity and mortality. OBJECTIVE: To classify distal pancreatectomy (DP) based on the extent of resection and technical difficulty and to evaluate postoperative outcomes with regards to this classification system. METHODS: All consecutive patients who had undergone DP between 2001 and 2020 in a high-volume pancreatic surgery center were included in this study. DPs were subclassified into 4 distinct categories reflecting the extent of resection and technical difficulty, including standard DP (type 1), DP with venous (type 2), multivisceral (type 3), or arterial resection (type 4). Patient characteristics, perioperative data, and postoperative outcomes were analyzed and compared among the 4 groups. RESULTS: A total of 2135 patients underwent DP. Standard DP was the most frequently performed procedure (64.8%). The overall 90-day mortality rate was 1.6%. Morbidity rates were higher in patients with additional vascular or multivisceral resections, and 90-day mortality gradually increased with the extent of resection from standard DP to DP with arterial resection (type 1: 0.7%; type 2: 1.3%; type 3: 3%; type 4: 8.7%; P <0.0001). Multivariable analysis confirmed the type of DP as an independent risk factor for 90-day mortality. CONCLUSIONS: Postoperative outcomes after DP depend on the extent of resection and correlate with the type of DP. The implementation of the 4-type classification system allows standardized reporting of surgical outcomes after DP improving comparability of future studies.

Preoperative Surgical or Endoscopic Bile Duct Drainage in Pancreatic Cancer.

BACKGROUND: Patients with pancreatic cancer and obstructive jaundice routinely undergo endoscopic stent placement (ES). It is well known that ES causes bacterial contamination and infectious complications after pancreatic resection. OBJECTIVE: To compare short-term outcomes and survival in patients undergoing pancreatic head resection after preoperative ES vs preoperative surgical drainage (SD) via T-tube insertion. METHODS: Patients with obstructive jaundice who underwent SD or ES from 2016 to 2022 were identified from a prospective database. Outcome analyses included microbiological bile contamination, overall morbidity and assessment of the overall complication burden using the Comprehensive Complication Index (CCI). Overall survival was investigated by Kaplan‒Meier analysis. RESULTS: A total of 55 patients with SD were identified and matched with 110 ES patients. After the primary intervention, ES patients experienced more complications (ES: 17.3% vs. SD: 3.6%; P=0.013). The overall complication burden after pancreatic resection was higher in ES patients than in SD patients (CCI: 27.2 vs. 19.9; P=0.022). Additionally, bacterial contamination of the bile was more frequent in ES patients compared to SD individuals (94.3% vs. 7.1%; P<0.001) with similar bacteria in 83.3% of postoperative abdominal infections in ES patients. While overall survival did not differ between the two groups, patients with postinterventional complications after ES had an impaired survival compared to those without complications (11.3 mo vs. 20.4 mo; P=0.03). CONCLUSION: SD for obstructive jaundice in resectable pancreatic cancer is associated with a lower overall complication burden. Additionally, patients with complications after ES experience worse overall survival. These findings indicate to rethink our standards of treatment of obstructive jaundice in patients with pancreatic cancer.

Modelling atopic dermatitis in healthy human skin for the characterization of topical compounds.

Suitable human models for the development and characterization of topical compounds for inflammatory skin diseases such as atopic dermatitis are not readily available to date. We describe here the development of a translational model involving healthy human skin mimicking major aspects of AD and its application for the characterization of topical Janus kinase inhibitors. Full thickness human abdominal skin obtained from plastic surgery stimulated in vitro with IL4 and IL13 shows molecular features of AD. This is evidenced by STAT6 phosphorylation assessed by immunohistochemistry and analysis of skin lysates. Broad transcriptome changes assessed by AmpliSeq followed by gene set variation analysis showed a consistent upregulation of gene signatures characterizing AD in this model. Topical application of experimental formulations of compounds targeting the JAK pathway to full thickness skin normalizes the molecular features of AD induced by IL4 and IL13 stimulation. The inhibitory effects of topical JAK inhibitors on molecular features of AD are supported by pharmacokinetic analysis. The model described here is suited for the characterization of topical compounds for AD and has the potential to be extended to other inflammatory skin diseases and pathophysiological pathways.

Risk Factors for Rectal Stump Leakage After Discontinuity Resection: Stump Length Matters Most.

BACKGROUND: Discontinuity resection is commonly conducted to avoid anastomotic leakage in high-risk patients but potentially results in rectal stump leakage. Although risk factors for anastomotic leakage have been widely studied, data on rectal stump leakage rates and underlying risk factors are scarce. OBJECTIVE: To determine rectal stump leakage rates following Hartmann's procedure and to identify patient-and surgery-associated risk factors. DESIGN: A retrospective study with univariate and multivariate analyses was performed to identify risk factors of rectal stump leakage. A subgroup analysis of scheduled operations was performed. SETTINGS: The study was conducted at Heidelberg University Hospital, Germany. PATIENTS: Patients were included who underwent discontinuity resection with rectal stump formation between 2010 and 2020. MAIN OUTCOME MEASURES: The main outcome measures included rectal stump leakage rates, 30-day mortality, length of hospitalization, and necessity for further invasive treatment. RESULTS: Rectal stump leakage occurred in 11.78% of patients. Rectal stump leakage rates varied considerably depending on the surgical procedure performed and were highest following subtotal pelvic exenteration (34%). Diagnosis of rectal stump leakage peaked on postoperative day 7. A short rectal stump ( p = 0.001), previous pelvic radiotherapy ( p = 0.04), chemotherapy ( p = 0.004), and previous laparotomy ( p = 0.03) were independent risk factors for rectal stump leakage in the entire patient collective. In patients undergoing scheduled surgery, a short rectal stump was the only independent risk factor ( p = 0.003). Rectal stump leakage was not associated with increased 30-day mortality but prolonged length of hospitalization and frequently necessitated further invasive treatment. LIMITATIONS: Study results are limited by the retrospective design, a high number of emergency operations, and the mere inclusion of symptomatic leakages. CONCLUSIONS: Rectal stump leakage is a relevant complication after discontinuity resection. Risk factors should be considered during surgical decision-making when both discontinuity resection and abdominoperineal resection are feasible. See Video Abstract. FACTORES DE RIESGO PARA LA FUGA DEL MUN RECTAL DESPUS DE UNA RESECCIN POR DISCONTINUIDAD LA LONGITUD DEL MUN ES LO MS IMPORTANTE: ANTECEDENTES:La resección de discontinuidad se realiza comúnmente para evitar la fuga anastomótica en pacientes de alto riesgo, pero potencialmente da como resultado una fuga del muñón rectal. Si bien los factores de riesgo de fuga anastomótica se han estudiado ampliamente, los datos sobre las tasas de fuga del muñón rectal y los factores de riesgo subyacentes son escasos.OBJETIVO:Determinar las tasas de fuga del muñón rectal después del procedimiento de Hartmann e identificar los factores de riesgo asociados con el paciente y la cirugía.DISEÑO:Se realizó un estudio retrospectivo con análisis univariado y multivariado para identificar los factores de riesgo de fuga del muñón rectal. Se llevó a cabo un análisis de subgrupos de las operaciones programadas.AJUSTES:El estudio se realizó en el Hospital Universitario de Heidelberg, Alemania.PACIENTES:Se incluyeron pacientes que se sometieron a resección de discontinuidad con formación de muñón rectal entre 2010 y 2020.MEDIDAS DE RESULTADO PRINCIPALES:Las principales medidas de resultado incluyeron las tasas de fuga del muñón rectal, la mortalidad a los 30 días, la duración de la hospitalización y la necesidad de un tratamiento invasivo adicional.RESULTADOS:La fuga del muñón rectal ocurrió en el 11,78% de los pacientes. Las tasas de fuga del muñón rectal variaron considerablemente según el procedimiento quirúrgico realizado y fueron más altas después de la exenteración pélvica subtotal (34%). El diagnóstico de fuga del muñón rectal alcanzó su punto máximo en el día 7 del postoperatorio. Un muñón rectal corto (p = 0,001), radioterapia pélvica previa (p = 0,04), quimioterapia (p = 0,004) y laparotomía previa (p = 0,03) fueron factores de riesgo independientes de fuga rectal. Fuga del muñón en todo el colectivo de pacientes. En los pacientes sometidos a cirugía programada, el muñón rectal corto fue el único factor de riesgo independiente (p = 0,003). La fuga del muñón rectal no se asoció con un aumento de la mortalidad a los 30 días, pero con una duración prolongada de la hospitalización y con frecuencia requirió un tratamiento invasivo adicional.LIMITACIONES:Los resultados del estudio están limitados por el diseño retrospectivo, un alto número de operaciones de emergencia y la mera inclusión de fugas sintomáticas.CONCLUSIONES:La fuga del muñón rectal es una complicación relevante tras la resección por discontinuidad. Se deben considerar los factores de riesgo durante la toma de decisiones quirúrgicas cuando son factibles tanto la resección por discontinuidad como la resección abdominoperineal. (Traducción-Yesenia Rojas-Khalil ).

Inhibition of the Renin-Angiotensin System Improves Response to Neoadjuvant Therapy in Patients With Liver Metastasis of Colorectal Cancers.

INTRODUCTION: Renin-angiotensin-aldosterone system inhibitors (RAAS-I) have been shown to prolong overall survival in patients with liver metastasized colorectal cancer in combination with antiangiogenic treatment. The effects of RAAS-I combined with neoadjuvant chemotherapy on colorectal cancer liver metastasis remain unexplored. We aimed to study the response of patients undergoing liver resection to RAAS-I in combination with neoadjuvant therapy to elucidate their potential benefits. METHODS: Between February 2005 and May 2012, 62 patients fulfilled the inclusion criteria for distant metastasis (cM1) and comparable computed tomography or magnetic resonance tomography scans in the Picture Archiving Communication System of our center before and after neoadjuvant chemotherapy. Follow-up data and clinicopathological characteristics were collected from a prospective database and retrospectively investigated. The chemotherapeutic response to liver metastasis was evaluated according to the Response Evaluation Criteria in Solid Tumors criteria 1.1. RESULTS: Comparing the average reduction of measured lesions, a significant response to chemotherapy was detected in the patients receiving RAAS-I (n = 24) compared to those who did not (n = 38) (P = 0.031). Interestingly, the effect was more distinctive when the size reduction was compared between high responses with more than 50% size reduction of all measured lesions (P = 0.011). In the subgroup analysis of patients receiving bevacizumab treatment, high responses to chemotherapy were observed only in the RAAS-I cohort (28.6% versus 0%, P = 0.022). CONCLUSIONS: For neoadjuvantly treated patients, concomitant antihypertensive treatment with RAAS-I showed a higher total size reduction of liver metastasis as a sign of treatment response, especially in combination with antiangiogenic treatment with bevacizumab.

Carbon Dioxide Sensing by Immune Cells Occurs through Carbonic Anhydrase 2-Dependent Changes in Intracellular pH.

CO2, the primary gaseous product of respiration, is a major physiologic gas, the biology of which is poorly understood. Elevated CO2 is a feature of the microenvironment in multiple inflammatory diseases that suppresses immune cell activity. However, little is known about the CO2-sensing mechanisms and downstream pathways involved. We found that elevated CO2 correlates with reduced monocyte and macrophage migration in patients undergoing gastrointestinal surgery and that elevated CO2 reduces migration in vitro. Mechanistically, CO2 reduces autocrine inflammatory gene expression, thereby inhibiting macrophage activation in a manner dependent on decreased intracellular pH. Pharmacologic or genetic inhibition of carbonic anhydrases (CAs) uncouples a CO2-elicited intracellular pH response and attenuates CO2 sensitivity in immune cells. Conversely, CRISPR-driven upregulation of the isoenzyme CA2 confers CO2 sensitivity in nonimmune cells. Of interest, we found that patients with chronic lung diseases associated with elevated systemic CO2 (hypercapnia) display a greater risk of developing anastomotic leakage following gastrointestinal surgery, indicating impaired wound healing. Furthermore, low intraoperative pH levels in these patients correlate with reduced intestinal macrophage infiltration. In conclusion, CO2 is an immunomodulatory gas sensed by immune cells through a CA2-coupled change in intracellular pH.

Functional quality of life among newly diagnosed young adult colorectal cancer survivors compared to older adults: results from the ColoCare Study.

PURPOSE: Colorectal cancer (CRC) incidence and mortality are increasing among young adults (YAs) aged 18-39. This study compared quality of life (QOL) between YA and older adult CRC survivors in the ColoCare Study. METHODS: Participants were grouped by age (years) as follows: 18-39 (YA), 40-49, 50-64, and 65 + . Functional QOL (physical, social, role, emotional, cognitive) and global QOL were assessed with the EORTC-QLQ-C30 at enrollment, 3, 6, and 12 months. Average scores were compared between groups over time using longitudinal mixed-effect modeling. Proportions with clinically meaningful QOL impairment were calculated using age-relevant thresholds and compared between groups over time using logistic regression with mixed effects. RESULTS: Participants (N = 1590) were n = 81 YAs, n = 196 aged 40-49, n = 627 aged 50-64, and n = 686 aged 65 + . Average physical function was better among YAs than participants aged 50-64 (p = 0.010) and 65 + (p < 0.001), and average social function was worse among YAs than aged 65 + (p = 0.046). Relative to YAs, all age groups were less likely to report clinically meaningful social dysfunction (aged 40-49 OR = 0.13, 95%CI = 0.06-0.29; aged 50-64 OR = 0.10, 95%CI = 0.05-0.21; aged 65 + OR = 0.07, 95%CI = 0.04-0.15) and role dysfunction (aged 40-49 OR = 0.36, 95%CI = 0.18-0.75; aged 50-64 OR = 0.41, 95%CI = 0.22-0.78; aged 65 + OR = 0.32, 95%CI = 0.17-0.61). Participants aged 40-49 were also less likely to report physical dysfunction (OR = 0.42, 95%CI = 0.19-0.93). CONCLUSION: YA CRC survivors reported better physical and worse social function compared to older CRC survivors, and YA CRC survivors were more likely to report clinically meaningful social, role, and physical disfunction. Future work should further investigate QOL using age-relevant benchmarks to inform best practices for CRC survivorship care. TRIAL REGISTRATION: NCT02328677, registered December 2014.

The GIST of it all: management of gastrointestinal stromal tumors (GIST) from the first steps to tailored therapy. A bibliometric analysis.

PURPOSE: Improvement of patient care is associated with increasing publication numbers in biomedical research. However, such increasing numbers of publications make it challenging for physicians and scientists to screen and process the literature of their respective fields. In this study, we present a comprehensive bibliometric analysis of the evolution of gastrointestinal stromal tumor (GIST) research, analyzing the current state of the field and identifying key open questions going beyond the recent advantages for future studies to assess. METHODS: Using the Web of Science Core Collection, 5040 GIST-associated publications in the years 1984-2022 were identified and analyzed regarding key bibliometric variables using the Bibliometrix R package and VOSviewer software. RESULTS: GIST-associated publication numbers substantially increased over time, accentuated from year 2000 onwards, and being characterized by multinational collaborations. The main topic clusters comprise surgical management, tyrosine kinase inhibitor (TKI) development/treatment, diagnostic workup, and molecular pathophysiology. Within all main topic clusters, a significant progress is reflected by the literature over the years. This progress ranges from conventional open surgical techniques over minimally invasive, including robotic and endoscopic, resection techniques to increasing identification of specific functional genetic aberrations sensitizing for newly developed TKIs being extensively investigated in clinical studies and implemented in GIST treatment guidelines. However, especially in locally advanced, recurrent, and metastatic disease stages, surgery-related questions and certain specific questions concerning (further-line) TKI treatment resistance were infrequently addressed. CONCLUSION: Increasing GIST-related publication numbers reflect a continuous progress in the major topic clusters of the GIST research field. Especially in advanced disease stages, questions related to the interplay between surgical approaches and TKI treatment sensitivity should be addressed in future studies.

Risk factors and health behaviors associated with loneliness among cancer survivors during the COVID-19 pandemic.

Loneliness may exacerbate poor health outcomes particularly among cancer survivors during the COVID-19 pandemic. Little is known about the risk factors of loneliness among cancer survivors. We evaluated the risk factors of loneliness in the context of COVID-19 pandemic-related prevention behaviors and lifestyle/psychosocial factors among cancer survivors. Cancer survivors (n = 1471) seen at Huntsman Cancer Institute completed a survey between August-September 2020 evaluating health behaviors, medical care, and psychosocial factors including loneliness during COVID-19 pandemic. Participants were classified into two groups: 'lonely' (sometimes, usually, or always felt lonely in past month) and 'non-lonely' (never or rarely felt lonely in past month). 33% of cancer survivors reported feeling lonely in the past month. Multivariable logistic regression showed female sex, not living with a spouse/partner, poor health status, COVID-19 pandemic-associated lifestyle factors including increased alcohol consumption and marijuana/CBD oil use, and psychosocial stressors such as disruptions in daily life, less social interaction, and higher perceived stress and financial stress were associated with feeling lonely as compared to being non-lonely (all p < 0.05). A significant proportion of participants reported loneliness, which is a serious health risk among vulnerable populations, particularly cancer survivors. Modifiable risk factors such as unhealthy lifestyle behaviors and psychosocial stress were associated with loneliness. These results highlight the need to screen for unhealthy lifestyle factors and psychosocial stressors to identify cancer survivors at increased risk of loneliness and to develop effective management strategies.

Voltage sensor movements of CaV1.1 during an action potential in skeletal muscle fibers.

The skeletal muscle L-type Ca2+ channel (CaV1.1) works primarily as a voltage sensor for skeletal muscle action potential (AP)-evoked Ca2+ release. CaV1.1 contains four distinct voltage-sensing domains (VSDs), yet the contribution of each VSD to AP-evoked Ca2+ release remains unknown. To investigate the role of VSDs in excitation-contraction coupling (ECC), we encoded cysteine substitutions on each S4 voltage-sensing segment of CaV1.1, expressed each construct via in vivo gene transfer electroporation, and used in cellulo AP fluorometry to track the movement of each CaV1.1 VSD in skeletal muscle fibers. We first provide electrical measurements of CaV1.1 voltage sensor charge movement in response to an AP waveform. Then we characterize the fluorescently labeled channels' VSD fluorescence signal responses to an AP and compare them with the waveforms of the electrically measured charge movement, the optically measured free myoplasmic Ca2+, and the calculated rate of Ca2+ release from the sarcoplasmic reticulum for an AP, the physiological signal for skeletal muscle fiber activation. A considerable fraction of the fluorescence signal for each VSD occurred after the time of peak Ca2+ release, and even more occurred after the earlier peak of electrically measured charge movement during an AP, and thus could not directly reflect activation of Ca2+ release or charge movement, respectively. However, a sizable fraction of the fluorometric signals for VSDs I, II, and IV, but not VSDIII, overlap the rising phase of charge moved, and even more for Ca2+ release, and thus could be involved in voltage sensor rearrangements or Ca2+ release activation.

Is an intraoperative liver function assessment possible? Application of the 13C-methacetin-breath-test during major liver resections - a pilot study.

BACKGROUND: As prevention of posthepatectomy-liver-failure is crucial, there is need of dynamic assessment of liver function, even intraoperatively. 13C-methacetin-breath-test estimates the organ's microsomal functional capacity. This is its first intraoperative evaluation in major liver surgery. METHODS: 30 patients planed for resection of ≥3 liver segments, between March-November 2019, were prospectively enrolled in this "single-center", pilot study. Using the 13C-methacetin-breath-test, liver function was assessed four times: preoperatively, intraoperatively before and after resection and postoperatively. The resulted maximum-liver-function-capacity (LiMAx)-values and delta-over-baseline (DOB)-curves were compared, further analyzed and correlated to respective liver volumes. RESULTS: The intraoperative LiMAx-values before resection were mostly lower than the preoperative ones (-11.3% ± 28%). The intraoperative measurements after resection resulted to mostly higher values than the postoperative ones (42.35% ± 46.19%). Pharmacokinetically, an interference between the two intraoperative tests was observed. There was no strong correlation between residual liver volume and function with a percentual residual-LiMAx mostly lower than the percentual residual volume (-17.7% ± 4.1%). CONCLUSIONS: Intraoperative application of the 13C-methacetin-breath-test during major liver resections seems to deliver lower values than the standard preoperative test. As multiple intraoperative tests interfere significantly to each other, a single intraoperative measurement is suggested. Multicentric standardized measurements could define the "normal" range for intraoperative measurements and control their predictive value.

Genome-wide study of genetic polymorphisms predictive for outcome from first-line oxaliplatin-based chemotherapy in colorectal cancer patients.

We conducted the first large genome-wide association study to identify novel genetic variants that predict better (or poorer) prognosis in colorectal cancer patients receiving standard first-line oxaliplatin-based chemotherapy vs chemotherapy without oxaliplatin. We used data from two phase III trials, NCCTG N0147 and NCCTG N9741 and a population-based patient cohort, DACHS. Multivariable Cox proportional hazards models were employed, including an interaction term between each SNP and type of treatment for overall survival (OS) and progression-free survival. The analysis was performed for studies individually, and the results were combined using fixed-effect meta-analyses separately for resected stage III colon cancer (3098 patients from NCCTG N0147 and 549 patients from DACHS) and mCRC (505 patients from NCCTG N9741 and 437 patients from DACHS). We further performed gene-based analysis as well as in silico bioinformatics analysis for CRC-relevant functional genomic annotation of identified loci. In stage III colon cancer patients, a locus on chr22 (rs11912167) was associated with significantly poorer OS after oxaliplatin-based chemotherapy vs chemotherapy without oxaliplatin (Pinteraction < 5 × 10-8 ). For mCRC patients, three loci on chr1 (rs1234556), chr12 (rs11052270) and chr15 (rs11858406) were found to be associated with differential OS (P < 5 × 10-7 ). The locus on chr1 located in the intronic region of RCSD1 was replicated in an independent cohort of 586 mCRC patients from ALGB/SWOG 80405 (Pinteraction = .04). The GWA gene-based analysis yielded for RCSD1 the most significant association with differential OS in mCRC (P = 6.6 × 10-6 ). With further investigation into its biological mechanisms, this finding could potentially be used to individualize first-line treatment and improve clinical outcomes.

Distal Bile Duct Cancer: Radical (R0 > 1 mm) Resection Achieves Favorable Survival.

OBJECTIVE: Evaluation of the outcome after resection for distal bile duct cancer (DBC) with focus on the impact of microscopic histopathological resection status R0 (>1 mm) versus R1 (≤1 mm) vs R1 (direct). SUMMARY BACKGROUND DATA: DBC is a rare disease for which oncologic resection offers the only chance of cure. METHODS: Prospectively collected data of consecutive patients undergoing pancreaticoduodenectomy for DBC were analyzed. Histopathological resection status was classified according to the Leeds protocol for pancreatic ductal adeno carcinoma (PDAC) (PDAC; R0 >1 mm margin clearance vs R1 ≤1 mm vs R1 direct margin involvement). RESULTS: A total of 196 patients underwent pancreaticoduodenectomy for DBC. Microscopic complete tumor clearance (R0>1 mm) was achieved in 113 patients (58%). Median overall survival (OS) of the entire cohort was 37 months (5- and 10-year OS rate: 40% and 31%, respectively). After R0 resection, median OS increased to 78 months with a 5-year OS rate of 52%. Negative prognostic factors were age >70 years ( P < 0.0001, hazard ratio (HR) 2.48), intraoperative blood loss >1000 mL ( P = 0.0009, HR 1.99), pN1 and pN2 status ( P = 0.0052 and P = 0.0006, HR 2.14 and 2.62, respectively) and American Society of Anesthesiologists score >II ( P = 0.0259, HR 1.61). CONCLUSIONS: This is the largest European single-center study of surgical treatment for DBC and the first to investigate the prognostic impact of the revised PDAC resection status definition in DBC. The results show that this definition is valid in DBC and that "true" R0 resection (>1 mm) is a key factor for excellent survival. In contrast to PDAC, there was no survival difference between R1 (≤1 mm) and R1 (direct).

Portal Vein Resection in Pancreatic Cancer Surgery: Risk of Thrombosis and Radicality Determine Survival.

OBJECTIVE: To evaluate the outcomes of pancreatic cancer [pancreatic ductal adenocarcinoma (PDAC)] surgery with concomitant portal vein resection (PVR), focusing on the PVR type according to the International Study Group of Pancreatic Surgery (ISGPS). BACKGROUND: Surgery offers the only chance for cure in PDAC. PVR is often performed for borderline or locally advanced tumors. METHODS: Consecutive patients with PDAC operated between January 2006 and January 2018 were included. Clinicopathologic characteristics and outcomes were analyzed and tested for survival prediction. RESULTS: Of 2265 PDAC resections, 1571 (69.4%) were standard resections and 694 (30.6%) were resections with PVR, including 149 (21.5%) tangential resections with venorrhaphy (ISGPS type 1), 21 (3.0%) resections with patch reconstruction (type 2), 491 (70.7%) end-to-end anastomoses (type 3), and 33 (4.8%) resections with graft interposition (type 4). The 90-day mortality rate was 2.6% after standard resection and 6.3% after resection with PVR ( P <0.0001). Postoperative portal vein thrombosis and pancreas-specific surgical complications most frequently occurred after PVR with graft interposition (21.2% and 48.5%, respectively). In multivariable analysis, age 70 years and above, ASA stages 3/4, increased preoperative serum carbohydrate antigen 19-9, neoadjuvant treatment, total pancreatectomy, PVR, higher UICC stage, and R+ resections were significant negative prognostic factors for overall survival. Radical R0 (>1 mm) resection resulted in 23.3 months of median survival. CONCLUSIONS: This is the largest single-center, comparative cohort study of PVR in PDAC surgery, showing that postoperative morbidity correlates with the reconstruction type. When radical resection is achieved, thrombosis risk is outweighed by beneficial overall survival times of nearly 2 years.

Distal Pancreatectomy With En Bloc Celiac Axis Resection (DP-CAR) for Locally Advanced Pancreatic Cancer: A Safe and Effective Procedure.

OBJECTIVE: To determine perioperative and oncologic outcomes after distal pancreatectomy with en bloc resection of the celiac axis (DP-CAR). BACKGROUND: DP-CAR can be used in a selective group of patients to resect locally advanced pancreatic cancer involving the celiac axis or common hepatic artery without arterial reconstruction by preserving retrograde blood flow via the gastroduodenal artery to the liver and stomach. METHODS: We analyzed all consecutive patients who had undergone DP-CAR between May 2003 and April 2022 at a tertiary hospital specialized in pancreatic surgery and present one of the largest single-center studies. RESULTS: A total of 71 patients underwent DP-CAR. Additional venous resection (VR) of the mesenterico-portal axis was performed in 31 patients (44%) and multivisceral resection (MVR) in 42 patients (59%). Margin-free (R0) resection was achieved in 40 patients (56%). The overall 90-day mortality rate was 8.4% for the entire patient cohort. After a cumulated experience of 16 cases, the 90-day mortality dropped to 3.6% in the following 55 patients. Extended procedures with (+) additional MVR with or without (+/-) VR resulted in higher major morbidity (Clavien-Dindo ≥IIIB; standard DP-CAR: 19%; DP-CAR + MVR +/- VR: 36%) and higher 90-day mortality (standard DP-CAR: 0%; DP-CAR + MVR +/- VR: 11%). Median overall survival after DP-CAR was 28 months. CONCLUSIONS: DP-CAR is a safe and effective procedure but requires experience. Frequently, surgical resection has to be extended with MVR and VR to accomplish tumor resection, which results in promising oncologic outcomes. However, extended resections were associated with increased morbidity and mortality.

Pancreatic Surgery in Children: Complex, Safe and Effective.

OBJECTIVE: The aim of this study is to assess indications for and report outcomes of pancreatic surgery in pediatric patients. BACKGROUND: Indications for pancreatic surgery in children are rare and data on surgical outcomes after pediatric pancreatic surgery are scarce. METHODS: All children who underwent pancreatic surgery at a tertiary hospital specializing in pancreatic surgery between 2003 and 2022 were identified from a prospectively maintained database. Indications, surgical procedures, and perioperative as well as long-term outcomes were analyzed. RESULTS: In total, 73 children with a mean age of 12.8 years (range: 4 months-18 years) underwent pancreatic surgery during the observation period. Indications included chronic pancreatitis (n=35), pancreatic tumors (n=27), and pancreatic trauma (n=11). Distal pancreatectomy was the most frequently performed procedure (n=23), followed by pancreatoduodenectomy (n=19), duodenum-preserving pancreatic head resection (n=10), segmental pancreatic resection (n=7), total pancreatectomy (n=3), and others (n=11). Postoperative morbidity occurred in 25 patients (34.2%), including 7 cases (9.6%) with major complications (Clavien-Dindo≥III). There was no postoperative (90-day) mortality. The 5-year overall survival was 90.5%. The 5-year event-free survival of patients with chronic pancreatitis was 85.7%, and 69.0% for patients with pancreatic tumors. CONCLUSION: This is the largest single-center study on pediatric pancreatic surgery in a Western population. Pediatric pancreatic surgery can be performed safely. Centralization in pancreatic centers with high expertise in surgery of adult and pediatric patients is important as it both affords the benefits of pancreatic surgery experience and ensures that surgical management is adapted to the specific needs of children.