Azotobacter vinelandii scaffold protein NifU transfers iron to NifQ as part of the iron-molybdenum cofactor biosynthesis pathway for nitrogenase.

The Azotobacter vinelandii molybdenum nitrogenase obtains molybdenum from NifQ, a monomeric iron-sulfur molybdoprotein. This protein requires an existing [Fe-S] cluster to form a [Mo-Fe3-S4] group, which acts as specific molybdenum donor during nitrogenase FeMo-co biosynthesis. Here, we show biochemical evidence supporting the role of NifU as the [Fe-S] cluster donor. Protein-protein interaction studies involving apo-NifQ and as-isolated NifU demonstrated their interaction, which was only effective when NifQ lacked its [Fe-S] cluster. Incubation of apo-NifQ with [Fe4-S4]-loaded NifU increased the iron content of the former, contingent to both proteins being able to interact with one another. As a result of this interaction, a [Fe4-S4] cluster was transferred from NifU to NifQ. In A. vinelandii , NifQ was preferentially metalated by NifU rather than by the [Fe-S] cluster scaffold protein IscU. These results indicate the necessity of co-expressing NifU and NifQ to efficiently provide molybdenum for FeMo-co biosynthesis when engineering nitrogenase in plants.

Harmonizing Definitions and Perspectives in Extreme Liver Surgery: A Delphi Experts Consensus.

OBJECTIVE: To propose to our community a common language about extreme liver surgery. BACKGROUND: The lack of a clear definition of extreme liver surgery prevents convincing comparisons of results among centers. METHODS: We used a two-round Delphi methodology to quantify consensus among liver surgery experts. For inclusion in the final recommendations, we established a consensus when the positive responses (agree and totally agree) exceeded 70%. The study steering group summarized and reported the recommendations. In general, a five-point Likert scale with a neutral central value was used, and in a few cases multiple choices. Results are displayed as numbers and percentages. RESULTS: A two-round Delphi study was completed by 38 expert surgeons in complex hepatobiliary surgery. The surgeon´s median age was 58 years old (52-63) and the median years of experience was 25 years (20-31). For the proposed definitions of total vascular occlusion, hepatic flow occlusion and inferior vein occlusion, the degree of agreement was 97%, 81% and 84%, respectively. In situ approach (64%) was the preferred, followed by ante situ (22%) and ex situ (14%). Autologous or cadaveric graft for hepatic artery or hepatic vein repair were the most recommended (89%). The use of veno-venous bypass or portocaval shunt revealed the divergence depending on the case. Overall, 75% of the experts agreed with the proposed definition for extreme liver surgery. CONCLUSION: Obtaining a consensus on the definition of extreme liver surgery is essential to guarantee the correct management of patients with highly complex hepatobiliary oncological disease. The management of candidates for extreme liver surgery involves comprehensive care ranging from adequate patient selection to the appropriate surgical strategy.

Cost-effectiveness of robotic vs laparoscopic distal pancreatectomy. Results from the national prospective trial ROBOCOSTES.

INTRODUCTION: Although several studies report that the robotic approach is more costly than laparoscopy, the cost-effectiveness of robotic distal pancreatectomy (RDP) over laparoscopic distal pancreatectomy (LDP) is still an issue. This study evaluates the cost-effectiveness of the RDP and LDP approaches across several Spanish centres. METHODS: This study is an observational, multicenter, national prospective study (ROBOCOSTES). For one year from 2022, all consecutive patients undergoing minimally invasive distal pancreatectomy were included, and clinical, QALY, and cost data were prospectively collected. The primary aim was to analyze the cost-effectiveness between RDP and LDP. RESULTS: During the study period, 80 procedures from 14 Spanish centres were analyzed. LDP had a shorter operative time than the RDP approach (192.2 min vs 241.3 min, p = 0.004). RDP showed a lower conversion rate (19.5% vs 2.5%, p = 0.006) and a lower splenectomy rate (60% vs 26.5%, p = 0.004). A statistically significant difference was reported for the Comprehensive Complication Index between the two study groups, favouring the robotic approach (12.7 vs 6.1, p = 0.022). RDP was associated with increased operative costs of 1600 euros (p < 0.031), while overall cost expenses resulted in being 1070.92 Euros higher than the LDP but without a statistically significant difference (p = 0.064). The mean QALYs at 90 days after surgery for RDP (0.9534) were higher than those of LDP (0.8882) (p = 0.030). At a willingness-to-pay threshold of 20,000 and 30,000 euros, there was a 62.64% and 71.30% probability that RDP was more cost-effective than LDP, respectively. CONCLUSIONS: The RDP procedure in the Spanish healthcare system appears more cost-effective than the LDP.

AnfO controls fidelity of nitrogenase FeFe protein maturation by preventing misincorporation of FeV-cofactor.

Azotobacter vinelandii produces three genetically distinct, but structurally and mechanistically similar nitrogenase isozymes designated as Mo-dependent, V-dependent, or Fe-only based on the heterometal contained within their associated active site cofactors. These catalytic cofactors, which provide the site for N2 binding and reduction, are, respectively, designated as FeMo-cofactor, FeV-cofactor, and FeFe-cofactor. Fe-only nitrogenase is a poor catalyst for N2 fixation, when compared to the Mo-dependent and V-dependent nitrogenases and is only produced when neither Mo nor V is available. Under conditions favoring the production of Fe-only nitrogenase a gene product designated AnfO preserves the fidelity of Fe-only nitrogenase by preventing the misincorporation of FeV-cofactor, which results in the accumulation of a hybrid enzyme that cannot reduce N2 . These results are interpreted to indicate that AnfO controls the fidelity of Fe-only nitrogenase maturation during the physiological transition from conditions that favor V-dependent nitrogenase utilization to Fe-only nitrogenase utilization to support diazotrophic growth.

Light and shadow of watch-and-wait strategy in rectal cancer: oncological result, clinical outcomes, and cost-effectiveness analysis.

BACKGROUND: The watch-and-wait (WW) strategy is a potential option for patients with rectal cancer who obtain a complete clinic response after neoadjuvant therapy. The aim of this study is to analyze the long-term oncological outcomes and perform a cost-effectiveness analysis in patients undergoing this strategy for rectal cancer. MATERIAL AND METHODS: The data of patients treated with the WW strategy were prospectively collected from January 2015 to January 2020. A control group was created, matched 1:1 from a pool of 480 patients undergoing total mesorectal excision. An independent company carried out the financial analysis. Clinical and oncological outcomes were analyzed in both groups. Outcome parameters included surgical and follow-up costs, quality-adjusted life years (QALYs), and the incremental cost per QALY gained or the incremental cost-effectiveness ratio (ICER). RESULTS: Forty patients were included in the WW group, with 40 patients in the surgical group. During a median follow-up period of 36 months, metastasis-free survival (MFS) and overall survival (OS) were similar in the two groups. In the WW group, nine (22%) local regrowths were detected in the first 2 years. The permanent stoma rate was slightly higher after salvage surgery in the WW group compared to the surgical group (48.5% vs 20%, p < 0.01). The cost-effectiveness analysis was slightly better for the WW group, especially for low rectal cancer compared to medium-high rectal cancer (ICER = - 108,642.1 vs ICER = - 42,423). CONCLUSIONS: The WW strategy in locally advanced rectal cancer offers similar oncological outcomes with respect to the surgical group and excellent results in quality of life and cost outcomes, especially for low rectal cancer. Nonetheless, the complex surgical field during salvage surgery can lead to a high permanent stoma rate; therefore, the careful selection of patients is mandatory.

Can 3D imaging modeling recognize functional tissue and predict liver failure? A retrospective study based on 3D modelling of the major hepatectomies after hepatic modulation.

BACKGROUND: Thanks to the introduction of radiomics, 3d reconstruction can be able to analyse tissues and recognise true hypertrophy from non-functioning tissue in patients treated with major hepatectomies with hepatic modulation.The aim of this study is to evaluate the performance of 3D Imaging Modelling in predict liver failure. METHODS: Patients submitted to major hepatectomies after hepatic modulation at Sanchinarro University Hospital from May 2015 to October 2019 were analysed. Three-dimensional reconstruction was realised before and after surgical treatment. The volumetry of Future Liver Remnant was calculated, distinguishing in Functional Future Liver Remnant (FRFx) i.e. true hypertrophy tissue and Anatomic Future Liver Remnant (FRL) i.e. hypertrophy plus no functional tissue (oedema/congestion) These volumes were analysed in patients with and without post hepatic liver failure. RESULTS: Twenty-four procedures were realised (11 ALPPS and 13 PVE followed by major hepatectomy). Post hepatic liver failure grade B and C occurred in 6 patients. The ROC curve showed a better AUC for FRFxV (74%) with respect to FRLV (54%) in prediction PHLF > B. The increase of anatomical FRL (iFRL) was superior in the ALPPS group (120%) with respect to the PVE group (73%) (p = 0,041), while the increase of functional FRFX (iFRFx) was 35% in the ALLPS group and 46% in the PVE group (p > 0,05), showing no difference in the two groups. CONCLUSION: The 3D reconstruction model can allow optimal surgical planning, and through the use of specific algorithms, can contribute to differential functioning liver parenchyma of the FLR.

Liver prometastatic reaction: Stimulating factors and responsive cancer phenotypes.

Cancer is first a localized tissue disorder, whose soluble and exosomal molecules and invasive cells induce a host response providing the stromal components of the primary tumor microenvironment (TME). Once the TME is developed, cancer-derived molecules and cells can more efficiently spread out and a whole-body response takes place, whose pathophysiological changes may result in a paraneoplastic syndrome. Remote organ-specific prometastatic reactions may also occur at this time, facilitating metastatic activities of circulating tumor cells (CTCs) through premetastatic niche development at targeted organs. However, additional signaling factors from the inter-organ communication network involved in the pathophysiology and comorbidities of cancer patients may also regulate prometastatic reaction-stimulating effects of cancer and non-cancer tissue factors. This article provides a conceptual overview of our ongoing clinical research on the liver prometastatic reaction (LPR) of patients with colorectal cancer (CRC), their portal vein- and hepatic artery-driven LPR-Stimulating Factors (LPR-SF), and their resulting LPR-derived Metastasis-Stimulating Factors (LPR-MSF) acting on liver-invading CRC cells. In addition, we also provide new insights on the molecular subtyping of LPR-responsive cancer phenotypes in patients with CRC and melanoma; and on how to investigate and interpret the prometastatic infrastructure in the real pathophysiological context of patients with cancer undergoing surgical procedures and receiving pharmacological treatments with multiple side effects, including those affecting the LPR, its stimulating factors and responsive cancer phenotypes.

Liver growth prediction in ALPPS - A multicenter analysis from the international ALPPS registry.

BACKGROUND: While ALPPS triggers a fast liver hypertrophy, it is still unclear which factors matter most to achieve accelerated hypertrophy within a short period of time. The aim of the study was to identify patient-intrinsic factors related to the growth of the future liver remnant (FLR). METHODS: This cohort study is composed of data derived from the International ALPPS Registry from November 2011 and October 2018. We analyse the influence of demographic, tumour type and perioperative data on the growth of the FLR. The volume of the FLR was calculated in millilitre and percentage using computed-tomography (CT) scans before and after stage 1, both according to Vauthey formula. RESULTS: A total of 734 patients were included from 99 centres. The median sFLR at stage 1 and stage 2 was 0.23 (IQR, 0.18-0.28) and 0.39 (IQR: 0.31-0.46), respectively. The variables associated with a lower increase from sFLR1 to sFLR2 were age˃68 years (p = .02), height ˃1.76 m (p ˂ .01), weight ˃83 kg (p ˂ .01), BMI˃28 (p ˂ .01), male gender (p ˂ .01), antihypertensive therapy (p ˂ .01), operation time ˃370 minutes (p ˂ .01) and hospital stay˃14 days (p ˂ .01). The time required to reach sufficient volume for stage 2, male gender accounts 40.3% in group ˂7 days, compared with 50% of female, and female present 15.3% in group ˃14 days compared with 20.6% of male. CONCLUSIONS: Height, weight, FLR size and gender could be the variables that most constantly influence both daily growths, the interstage increase and the standardized FLR before the second stage.

Biosynthesis of Nitrogenase Cofactors.

Nitrogenase harbors three distinct metal prosthetic groups that are required for its activity. The simplest one is a [4Fe-4S] cluster located at the Fe protein nitrogenase component. The MoFe protein component carries an [8Fe-7S] group called P-cluster and a [7Fe-9S-C-Mo-R-homocitrate] group called FeMo-co. Formation of nitrogenase metalloclusters requires the participation of the structural nitrogenase components and many accessory proteins, and occurs both in situ, for the P-cluster, and in external assembly sites for FeMo-co. The biosynthesis of FeMo-co is performed stepwise and involves molecular scaffolds, metallochaperones, radical chemistry, and novel and unique biosynthetic intermediates. This review provides a critical overview of discoveries on nitrogenase cofactor structure, function, and activity over the last four decades.

Biosynthesis of the nitrogenase active-site cofactor precursor NifB-co in Saccharomyces cerevisiae.

The radical S-adenosylmethionine (SAM) enzyme NifB occupies a central and essential position in nitrogenase biogenesis. NifB catalyzes the formation of an [8Fe-9S-C] cluster, called NifB-co, which constitutes the core of the active-site cofactors for all 3 nitrogenase types. Here, we produce functional NifB in aerobically cultured Saccharomyces cerevisiae Combinatorial pathway design was employed to construct 62 strains in which transcription units driving different expression levels of mitochondria-targeted nif genes (nifUSXB and fdxN) were integrated into the chromosome. Two combinatorial libraries totaling 0.7 Mb were constructed: An expression library of 6 partial clusters, including nifUSX and fdxN, and a library consisting of 28 different nifB genes mined from the Structure-Function Linkage Database and expressed at different levels according to a factorial design. We show that coexpression in yeast of the nitrogenase maturation proteins NifU, NifS, and FdxN from Azotobacter vinelandii with NifB from the archaea Methanocaldococcus infernus or Methanothermobacter thermautotrophicus yields NifB proteins equipped with [Fe-S] clusters that, as purified, support in vitro formation of NifB-co. Proof of in vivo NifB-co formation was additionally obtained. NifX as purified from aerobically cultured S. cerevisiae coexpressing M. thermautotrophicus NifB with A. vinelandii NifU, NifS, and FdxN, and engineered yeast SAM synthase supported FeMo-co synthesis, indicative of NifX carrying in vivo-formed NifB-co. This study defines the minimal genetic determinants for the formation of the key precursor in the nitrogenase cofactor biosynthetic pathway in a eukaryotic organism.

Right-side colectomy with complete mesocolic excision vs conventional right-side colectomy in the treatment of colon cancer: a systematic review and meta-analysis.

BACKGROUND: This meta-analysis aims to investigate the role of complete mesocolic excision (CME) in the treatment of right-side colon cancer when compared with standard right-side hemicolectomy, focusing on oncological outcomes, mortality and morbidity rates. MATERIALS AND METHODS: A systematic literature search was performed on MEDLINE and EMBASE archives, including studies on CME in right-side colon cancer. Primary outcomes were five-year disease-free survival and five-year overall survival. Secondary outcomes investigated were mortality and morbidity rates, intraoperative blood loss, anastomotic leakage, postoperative ileus, day of postoperative flatus, pulmonary infection, duration of hospital stay and number of lymph nodes harvested. RESULTS: Seventeen studies have been included in this meta-analysis for a total of 3918 patients. The five-year disease-free survival (DFS) and overall survival (OS) results improved in the CME group with respect to conventional right-side colectomy with an OR 1.88 (95% CI 1.02-3.45) and OR 2.77 (95% CI 1.33-5.74), respectively. The incidence of mortality and morbidity was comparable between the two groups. Moreover, conventional surgery time was faster than CME (MD 33.69 min, 95% CI 12.79-54.59), while no significant differences were reported in mean blood loss and hospital stay. Furthermore, the CME group showed a higher mean number of harvested lymph nodes (MD 7.08 lymph nodes 95% CI 4.90-9.27). CONCLUSION: Complete mesocolic excision of the right-side colectomy improves oncological outcomes without increasing mortality and morbidity rates compared to standard right-side hemicolectomy. CME should therefore be routinely performed in the treatment of right-side colon cancer.

Preoperative hepatic artery embolization before distal pancreatectomy plus celiac axis resection does not improve surgical results: A Spanish multicentre study.

BACKGROUND: Distal pancreatectomy with celiac axis resection (DP-CAR) is a surgical procedure with high morbidity and mortality performed in patients with locally advanced pancreatic cancer. Preoperative embolization of hepatic artery (PHAE) has been postulated as a technical option to increase resection rate. OBJECTIVE: comparison of morbidity and mortality at 90 days, operative time, hospital stay and survival between patients that performed DP-CAR with and without PHAE. METHODS: Observational retrospective multicentre study. INCLUSION CRITERIA: patient operated in Spanish centers with DP-CAR for pancreatic cancer from April 2004 until 23 June 2018. Preoperative (PHAE, neodjuvant treatment), intraoperative (operative time and blood loss) and postoperative data (morbidity, hospital stay, R0 and survival) were studied. Complications were measured with Clavien classification at 90 days. Specific pancreatic complications were measured using ISGPS classifications. Data were analyzed using R version 3.1.3 (http://www.r-project.org). Level of significance was set at 0.05. RESULTS: 41 patients were studied. 26 patients were not embolized (NO-PHAE group) and 15 patients received PHAE. Preoperative BMI and percentage of neoadjuvant chemotherapy were the only preoperative variables different between both groups. The operative time in the PHAE group was shorter (343 min) than in the non-PHAE group (411 min) (p < 0.06). Major morbidity (Clavien > IIIa) and mortality at 90 days were higher in the PHAE group than in the non-PHAE group (60% vs 23% and 26.6% vs 11.6% respectively) (p < 0.004). No statistical difference in overall survival was observed between both groups (p = 0.14). CONCLUSION: In our study PHAE is not related with less postoperative morbidity. Even more, major morbidity (Clavien III-IV) and mortality was higher in PHAE group.

Variation in complications and mortality following ALPPS at early-adopting centers.

BACKGROUND: Various, often conflicting, estimates for post-operative morbidity and mortality following ALPPS have been reported in the literature, suggesting that considerable center-level variation exists. Some of this variation may be related to center volume and experience. METHODS: Using data from seventeen centers who were early adopters of the ALPPS technique, we estimated the variation, by center, in standardized 90-day mortality and comprehensive complication index (CCI) for patients treated between 2012 and 2018. RESULTS: We estimated that center-specific 90-day mortality following treatment with ALPPS varied from 4.2% (95% CI: 0.8, 9.9) to 29.1% (95% CI: 13.9, 50.9), and that center-specific CCI following treatment with ALPPS varied from 17.0 (95% CI: 7.5, 26.5) to 49.8 (95% CI: 38.1, 61.8). Declines in estimated 90-day mortality and CCI were observed over time, and almost all individual centers followed this trend. Patients treated at centers with a higher number of ALPPS cases performed over the prior year had a lower risk of post-operative mortality. CONCLUSION: Despite considerable center-level variation in ALPPS outcomes, perioperative outcomes following ALPPS have improved over time and treatment at higher volume centers results in a lower risk of 90-day mortality. Morbidity and mortality remain concerningly high at some centers.

The NifZ accessory protein has an equivalent function in maturation of both nitrogenase MoFe protein P-clusters.

The Mo-dependent nitrogenase comprises two interacting components called the Fe protein and the MoFe protein. The MoFe protein is an α2ß2 heterotetramer that harbors two types of complex metalloclusters, both of which are necessary for N2 reduction. One type is a 7Fe-9S-Mo-C-homocitrate species designated FeMo-cofactor, which provides the N2-binding catalytic site, and the other is an 8Fe-7S species designated the P-cluster, involved in mediating intercomponent electron transfer to FeMo-cofactor. The MoFe protein's catalytic partner, Fe protein, is also required for both FeMo-cofactor formation and the conversion of an immature form of P-clusters to the mature species. This latter process involves several assembly factors, NafH, NifW, and NifZ, and precedes FeMo-cofactor insertion. Here, using various protein affinity-based purification methods as well as in vivo, EPR spectroscopy, and MALDI measurements, we show that several MoFe protein species accumulate in a NifZ-deficient background of the nitrogen-fixing microbe Azotobacter vinelandii These included fully active MoFe protein replete with FeMo-cofactor and mature P-cluster, inactive MoFe protein having no FeMo-cofactor and only immature P-cluster, and partially active MoFe protein having one αß-unit with a FeMo-cofactor and mature P-cluster and the other αß-unit with no FeMo-cofactor and immature P-cluster. Also, NifW could associate with MoFe protein having immature P-clusters and became dissociated upon P-cluster maturation. Furthermore, both P-clusters could mature in vitro without NifZ. These findings indicate that NifZ has an equivalent, although not essential, function in the maturation of both P-clusters contained within the MoFe protein.

ALPPS for Locally Advanced Intrahepatic Cholangiocarcinoma: Did Aggressive Surgery Lead to the Oncological Benefit? An International Multi-center Study.

BACKGROUND: ALPPS is found to increase the resectability of primary and secondary liver malignancy at the advanced stage. The aim of the study was to verify the surgical and oncological outcome of ALPPS for intrahepatic cholangiocarcinoma (ICC). METHODS: The study cohort was based on the ALPPS registry with patients from 31 international centers between August 2009 and January 2018. Propensity score matched patients receiving chemotherapy only were selected from the SEER database as controls for the survival analysis. RESULTS: One hundred and two patients undergoing ALPPS were recruited, 99 completed the second stage with median inter-stage duration of 11 days. The median kinetic growth rate was 23 ml/day. R0 resection was achieved in 87 (85%). Initially high rates of morbidity and mortality decreased steadily to a 29% severe complication rate and 7% 90-day morbidity in the last 2 years. Post-hepatectomy liver failure remained the main cause of 90-day mortality. Multivariate analysis revealed insufficient future liver remnant at the stage-2 operation (FLR2) to be the only risk factor for severe complications (OR 2.91, p = 0.02). The propensity score matching analysis showed a superior overall survival in the ALPPS group compared to palliative chemotherapy (median overall survival: 26.4 months vs 14 months; 1-, 2-, and 3-year survival rates: 82.4%, 70.5% and 39.6% vs 51.2%, 21.4% and 11.3%, respectively, p < 0.01). The survival benefit, however, was not confirmed in the subgroup analysis for patients with insufficient FLR2 or multifocal ICC. CONCLUSION: ALPPS showed high efficacy in achieving R0 resections in locally advanced ICC. To get the most oncological benefit from this aggressive surgery, ALPPS would be restricted to patients with single lesions and sufficient FLR2.

Prognostic Value of Lymph Node Status for Actual Long-Term Survival in Resected Pancreatic Cancer.

BACKGROUND: The prognostic factors for long-term survival after curative resection of pancreatic adenocarcinoma are still poorly understood. The purpose of this study was to identify the prognostic factors of long-term survival after resection of pancreatic adenocarcinoma based on actual 5-year survival including different lymph node status classifications. METHOD: A total of 106 patients who underwent pancreatectomy were enrolled at our institution and retrospectively analyzed according to actual survival (> vs < 5 years), as well as several currently available node classifications: N0/N1, N0/N1/N2, and lymph-node ratio (LNR) including multivariate logistic regression. RESULTS: The actual 5-year overall survival rate of the series was 12.26%. In a univariate analysis, operative blood loss and blood transfusion, completion of adjuvant treatment, histological differentiation, perineural invasion, N0/N1, N0/N1/N2 and LNR were significant predictive factors for actual long-term survival. A multivariate analysis showed that only N0/N1 was an independent predictive factor for actual 5-year survival (OR: 1.593; 0.730-1.325; p= 0.264). CONCLUSION: The nodal involved status is the strongest independent unfavorable factor for actual long-term survival after pancreatic resection for adenocarcinoma.

ALPPS in neuroendocrine liver metastases not amenable for conventional resection - lessons learned from an interim analysis of the International ALPPS Registry.

BACKGROUND: Surgery is the most effective treatment option for neuroendocrine liver metastases (NELM). This study investigated the role of associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) as a novel strategy in treatment of NELM. METHODS: The International ALPPS Registry was reviewed to study patients who underwent ALPPS for NELM. RESULTS: From 2010 to 2017, 954 ALPPS procedures from 135 international centers were recorded in the International ALPPS Registry. Of them, 24 (2.5%) were performed for NELM. Twenty-one patients entered the final analysis. Overall grade ≥3b morbidity was 9% after stage 1 and 27% after stage 2. Ninety-day mortality was 5%. R0 resection was achieved in 19 cases (90%) at stage 2. Median follow-up was 28 (19-48) months. Median disease free survival (DFS) was 17.3 (95% CI: 7.1-27.4) months, 1-year and 2-year DFS was 73.2% and 41.8%, respectively. Median overall survival (OS) was not reached. One-year and 2-year OS was 95.2% and 95.2%, respectively. CONCLUSIONS: ALPPS appears to be a suitable strategy for inclusion in the multimodal armamentarium of well-selected patients with neuroendocrine liver metastases. In light of the morbidity in this initial series and a high rate of disease-recurrence, the procedure should be taken with caution.

Sequential and differential interaction of assembly factors during nitrogenase MoFe protein maturation.

Nitrogenases reduce atmospheric nitrogen, yielding the basic inorganic molecule ammonia. The nitrogenase MoFe protein contains two cofactors, a [7Fe-9S-Mo-C-homocitrate] active-site species, designated FeMo-cofactor, and a [8Fe-7S] electron-transfer mediator called P-cluster. Both cofactors are essential for molybdenum-dependent nitrogenase catalysis in the nitrogen-fixing bacterium Azotobacter vinelandii We show here that three proteins, NafH, NifW, and NifZ, copurify with MoFe protein produced by an A. vinelandii strain deficient in both FeMo-cofactor formation and P-cluster maturation. In contrast, two different proteins, NifY and NafY, copurified with MoFe protein deficient only in FeMo-cofactor formation. We refer to proteins associated with immature MoFe protein in the following as "assembly factors." Copurifications of such assembly factors with MoFe protein produced in different genetic backgrounds revealed their sequential and differential interactions with MoFe protein during the maturation process. We found that these interactions occur in the order NafH, NifW, NifZ, and NafY/NifY. Interactions of NafH, NifW, and NifZ with immature forms of MoFe protein preceded completion of P-cluster maturation, whereas interaction of NafY/NifY preceded FeMo-cofactor insertion. Because each assembly factor could independently bind an immature form of MoFe protein, we propose that subpopulations of MoFe protein-assembly factor complexes represent MoFe protein captured at different stages of a sequential maturation process. This suggestion was supported by separate isolation of three such complexes, MoFe protein-NafY, MoFe protein-NifY, and MoFe protein-NifW. We conclude that factors involved in MoFe protein maturation sequentially bind and dissociate in a dynamic process involving several MoFe protein conformational states.

Percutaneous hepatic perfusion (chemosaturation) with melphalan in patients with intrahepatic cholangiocarcinoma: European multicentre study on safety, short-term effects and survival.

OBJECTIVES: Cholangiocarcinoma is the second most common primary liver tumour with a poor overall prognosis. Percutaneous hepatic perfusion (PHP) is a directed therapy for primary and secondary liver malignancies, and its efficacy and safety have been shown in different entities. The purpose of this study was to prove the safety and efficacy of PHP in patients with unresectable intrahepatic cholangiocarcinoma (iCCA). PATIENTS AND METHODS: We retrospectively reviewed data from 15 patients with unresectable iCCA treated with PHP in nine different hospitals throughout Europe. Overall response rates (ORR) were assessed according to response evaluation criteria in solid tumours (RECIST1.1). Overall survival (OS), progression-free survival (PFS) and hepatic PFS (hPFS) were analysed using the Kaplan-Meier estimation. Adverse events (AEs) and toxicity were evaluated. RESULTS: Fifteen patients were treated with 26 PHPs. ORR was 20%, disease control was achieved in 53% after the first PHP. Median OS was 26.9 months from initial diagnosis and 7.6 months from first PHP. Median PFS and hPFS were 122 and 131 days, respectively. Patients with liver-only disease had a significantly longer median OS compared to patients with locoregional lymph node metastases (12.9 vs. 4.8 months, respectively; p < 0.01). Haematological toxicity was common, but manageable. No AEs of grade 3 or 4 occurred during the procedures. DISCUSSION: PHP is a standardised and safe procedure that provides promising response rates and survival data in patients with iCCA, especially in non-metastatic disease. KEY POINTS: • Percutaneous hepatic perfusion (PHP) offers an additional locoregional therapy strategy for the treatment of unresectable primary or secondary intrahepatic malignancies. • PHP is a standardised and safe procedure that provides promising response rates and survival data in patients with intrahepatic cholangiocarcinoma (iCCA), especially in non-metastatic disease. • Side effects seem to be tolerable and comparable to other systemic or local treatment strategies.