Chromosome-level genome assembly and population genomic analysis provide insights into the genetic diversity and adaption of Schizopygopsis younghusbandi on the Tibetan Plateau.

The Yarlung Tsangpo River on the Tibetan Plateau provides a unique natural environment for studying fish evolution and ecology. However, the genomes and genetic diversity of plateau fish species have been rarely reported. Schizopygopsis younghusbandi, a highly specialized Schizothoracine species and economically important fish inhabiting the Yarlung Tsangpo River, is threatened by overfishing and biological invasion. Herein, we generated a chromosome-level genome of S. younghusbandi and whole-genome resequencing data for 59 individuals from six locations of the river. The results showed that the divergence time between S. younghusbandi and other primitive Schizothoracine species was ∼4.2 Mya, coinciding with the major phase of the Neogene Tibetan uplift. The expanded gene families enriched in DNA integration and replication, ion binding and transport, energy storage, and metabolism likely contribute to the adaption of this species. The S. younghusbandi may have diverged from other highly specialized Schizothoracine species in the Zanda basin during the Pliocene epoch, which underwent major population reduction possibly due to the drastic climate change during the last glacial period. Population analysis indicated that the ancient population might have originated upstream before gradually adapting to evolve into the populations inhabiting the mid-stream and downstream regions of the Yarlung Tsangpo River. In conclusion, the chromosome-level genome and population diversity of S. younghusbandi provide valuable genetic resources for the evolution, ecology, and conservation studies of endemic fishes on the Tibetan Plateau.

Protocol for Designing De Novo Noncanonical Peptide Binders in OSPREY.

D-peptides, the mirror image of canonical L-peptides, offer numerous biological advantages that make them effective therapeutics. This article details how to use DexDesign, the newest OSPREY-based algorithm, for designing these D-peptides de novo. OSPREY physics-based models precisely mimic energy-equivariant reflection operations, enabling the generation of D-peptide scaffolds from L-peptide templates. Due to the scarcity of D-peptide:L-protein structural data, DexDesign calls a geometric hashing algorithm, Method of Accelerated Search for Tertiary Ensemble Representatives, as a subroutine to produce a synthetic structural dataset. DexDesign enables mixed-chirality designs with a new user interface and also reduces the conformation and sequence search space using three new design techniques: Minimum Flexible Set, Inverse Alanine Scanning, and K*-based Mutational Scanning.

Novel loss-of-function variants in WDR26 cause Skraban-Deardorff syndrome in two Chinese patients.

Introduction: Mutations in the protein WD repeat structural domain 26 (WDR26, MIM 617424) have been identified as the cause of autosomal dominant Skraban-Deardorff syndrome, a rare genetic disorder characterized by intellectual disability (ID), developmental delay (DD), hypotonia, epilepsy, infant feeding difficulties, gait abnormalities and distinctive facial features. The objective of this study is to investigate the genetic factors that may contribute to the development of Skraban-Deardorff syndrome in affected individuals. Methods: In this study, we used whole-exome sequencing (WES) to analyze pathogenic and likely pathogenic variants in two unrelated Chinese patients with DD and ID. We confirmed the origin of the variants by conducting Sanger sequencing and classified them according to ACMG/AMP guidelines. Results: Here, two novel de novo variants (c.1797delC(p.His599fs*11) and c.1414C>T(p.Gln472*)) in the WDR26 gene have been identified in two Chinese patients with Skraban-Deardorff syndrome. These patients exhibit a range of symptoms, including varying degrees of ID, DD, speech delay, an abnormal wide-foot and/or stiff-legged gait, facial dysmorphism, behavioural abnormalities, with or without seizures. Conclusions: In this study, We report two unrelated Chinese patients with Skraban-Deardorff syndrome caused by novel de novo pathogenic variants of the WDR26 gene. These patients showed a clinical phenotype similar to that of patients with the WDR26 variant. Compared to reported cases with WDR26 pathogenic variants, patient 2 presented a novel complication of severe behavioural problems, including hyperactivity, social anxiety, self-mutilation, impulsivity and violent behaviour. This research broadens the range of genetic and clinical features of Skraban-Deardorff syndrome. In addition, the symptoms may become more pronounced as the patient ages. Furthermore, our report highlights the clinical diversity of Skraban-Deardorff syndrome. The findings may assist healthcare professionals in providing more accurate genetic testing and counselling to affected families and improving the overall management of the condition.

Guiding the starting dose of the once-daily formulation of tacrolimus in "de novo" adult renal transplant patients: a population approach.

Aims: The once-daily extended-release tacrolimus formulation (ER-Tac) has demonstrated similar efficacy and safety to the twice-daily immediate-release formulation (IR-Tac), but few population-based pharmacokinetic models have been developed in de novo kidney transplant patients to optimize doses. Therefore, this study aimed i) at developing a population pharmacokinetic model for ER-Tac in de novo adult kidney transplant patients ii) and identifying genetic factors and time-varying covariates predictive of pharmacokinetic variability to guide tacrolimus dosage during the early post-transplant period. Methods: A total of 1,067 blood tacrolimus concentrations from 138 kidney transplant patients were analyzed. A total of 29 out of 138 patients were intensively sampled for 24 h on the day 5 post-transplantation; meanwhile, for the remaining patients, concentrations were collected on days 5, 10, and 15 after transplantation. Tacrolimus daily doses and genetic and demographic characteristics were retrieved from the medical files. Biochemistry time-varying covariates were obtained on different days over the pharmacokinetic (PK) study. A simultaneous PK analysis of all concentrations was carried out using the non-linear mixed-effects approach with NONMEM 7.5. Results: A two-compartment model with linear elimination and delayed absorption best described the tacrolimus pharmacokinetics. Between-patient variability was associated with oral blood clearance (CL/F) and the central compartment distribution volume (Vc/F). Tacrolimus concentrations standardized to a hematocrit value of 45% significantly improved the model (p < 0.001). This method outperformed the standard covariate modeling of the hematocrit-blood clearance relationship. The effect of the CYP3A5 genotype was statistically (p < 0.001) and clinically significant on CL/F. The CL/F of patients who were CYP3A5*1 carriers was 51% higher than that of CYP3A5*1 non-carriers. Age also influenced CL/F variability (p < 0.001). Specifically, CL/F declined by 0.0562 units per each increased year from the value estimated in patients who were 60 years and younger. Conclusion: The 36% between-patient variability in CL/F was explained by CYP3A5 genotype, age, and hematocrit. Hematocrit standardization to 45% explained the variability of tacrolimus whole-blood concentrations, and this was of utmost importance in order to better interpret whole-blood tacrolimus concentrations during therapeutic drug monitoring. The dose requirements of CYP3A5*/1 carriers in patients aged 60 years or younger would be highest, while CYP3A5*/1 non-carriers older than 60 years would require the lowest doses.

Lipidomics reveals the lipid-lowering and hepatoprotective effects of Celosia Semen on high-fat diet-induced NAFLD mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Celosia Semen (CS) serves as a traditional Chinese medicine (TCM) for promoting liver health and enhancing vision, with extensive clinical applications. Triterpenoid saponins represent the primary active components of CS, with the highest concentration of Celosin I (CI) detected. The urgent need for effective NAFLD treatments motivated us assess the beneficial effects of total saponins from CS (TSCS) and CI. AIMS OF THE STUDY: To investigate the therapeutic effects of TSCS and CI on NAFLD and its underlying molecular mechanisms. MATERIALS AND METHODS: The impact of TSCS and CI on NAFLD was evaluated through in vitro and in vivo methodologies, utilizing high-fat diet (HFD) and palmitic acid/oleic acid modeling on C57BL/6J mice and AML12 cells, respectively. Biochemical analysis, H&E and Oil red O staining were used to characterize the lipid-lowering and hepatoprotective activities of TSCS and CI. Lipidomics discerned the impact of TSCS and CI interventions on liver lipid composition, distribution and alteration in NFALD mice. RT-qPCR and western blotting detected the influence of TSCS and CI on genes linked to de novo lipogenesis, fat calculation uptake, oxidation and esterification. The docking analysis anticipated the interaction of six major triterpenoid saponins within TSCS with SREBP1. RESULTS: TSCS and CI markedly diminished lipid accumulation induced by high fat both in vivo and in vitro. TSCS and CI also mitigated hepatic steatosis and liver injury induced by HFD through the reduction of TC, TG, FAs, ALT, and AST, even at minimal dose of 25 mg/kg. Lipidomics indicated that TSCS and CI had the potential to modulate the lipid metabolism network, rectify lipid metabolic dysregulation induced by NAFLD, decrease the levels of harmful lipids, and elevate the levels of advantageous lipids. Furthermore, TSCS and CI exhibited a strong affinity to SREBP1, thereby might directly influence the expression of SREBP1 and a cascade of essential enzymes involved in de novo lipogenesis, and finally resulting in a diminished synthesis of novel lipids. CONCLUSION: TSCS and CI were confirmed firstly as key active components of CS in amending hepatic steatosis and mitigate liver damage in NAFLD, outlining the preliminary mechanism. They warrant further exploration as drug candidates for NAFLD treatment, especially in light of the current shortage of medications and limited therapeutic options.

Graphasing: phasing diploid genome assembly graphs with single-cell strand sequencing.

Haplotype information is crucial for biomedical and population genetics research. However, current strategies to produce de novo haplotype-resolved assemblies often require either difficult-to-acquire parental data or an intermediate haplotype-collapsed assembly. Here, we present Graphasing, a workflow which synthesizes the global phase signal of Strand-seq with assembly graph topology to produce chromosome-scale de novo haplotypes for diploid genomes. Graphasing readily integrates with any assembly workflow that both outputs an assembly graph and has a haplotype assembly mode. Graphasing performs comparably to trio phasing in contiguity, phasing accuracy, and assembly quality, outperforms Hi-C in phasing accuracy, and generates human assemblies with over 18 chromosome-spanning haplotypes.

A case of de novo extra-stent ulceration induced by persistent plaque protrusion after carotid artery stenting with a CASPER stent for a large-volume unstable plaque.

Plaque protrusion (PP) has been identified as a perioperative complication of carotid artery stenosis treated with carotid artery stenting (CAS). The CASPER stent (CS), a dual-layer micromesh stent, may be able to prevent PP. Despite using CS, de novo extra-stent ulceration induced by persistent PP is rare. A 75-year-old male patient, whose superficial temporal artery-middle cerebral artery bypass tended to occlude, underwent CAS using a CS for symptomatic pseudo-occlusive internal carotid artery with a large-volume unstable plaque. This led to de novo extra-stent ulceration induced by persistent PP, resulting in ischemic stroke that necessitated the application of the stent-in-stent technique. There was no recurrence of cerebral infarction postoperatively at 12 months. Here, we present, to the best of our knowledge, the first case of a patient with de novo extra-stent ulceration induced by persistent PP after CAS that led to de novo extra-stent ulceration. The inhibition of intimal formation on the stent surface caused by persistent PP was considered to be the underlying mechanism. The stent-in-stent technique is beneficial even in cases of PP accompanied by de novo extra-stent ulceration.

High-Risk HLA-DQ Mismatches Are Associated With Adverse Outcomes After Lung Transplantation.

Human leukocyte antigen (HLA) mismatches (MM) between donor and recipient lead to eplet MM (epMM) in lung transplantation (LTX), which can induce the development of de-novo donor-specific HLA-antibodies (dnDSA), particularly HLA-DQ-dnDSA. Aim of our study was to identify risk factors for HLA-DQ-dnDSA development. We included all patients undergoing LTX between 2012 and 2020. All recipients/donors were typed for HLA 11-loci. Development of dnDSA was monitored 1-year post-LTX. EpMM were calculated using HLAMatchmaker. Differences in proportions and means were compared using Chi2-test and Students' t-test. We used Kaplan-Meier curves with LogRank test and multivariate Cox regression to compare acute cellular rejection (ACR), chronic lung allograft dysfunction (CLAD) and survival. Out of 183 patients, 22.9% patients developed HLA-DQ-dnDSA. HLA-DQ-homozygous patients were more likely to develop HLA-DQ-dnDSA than HLA-DQ-heterozygous patients (p = 0.03). Patients homozygous for HLA-DQ1 appeared to have a higher risk of developing HLA-DQ-dnDSA if they received a donor with HLA-DQB1*03:01. Several DQ-eplets were significantly associated with HLA-DQ-dnDSA development. In the multivariate analysis HLA-DQ-dnDSA was significantly associated with ACR (p = 0.03) and CLAD (p = 0.01). HLA-DQ-homozygosity, several high-risk DQ combinations and high-risk epMM result in a higher risk for HLA-DQ-dnDSA development which negatively impact clinical outcomes. Implementation in clinical practice could improve immunological compatibility and graft outcomes.

Exploring "dark-matter" protein folds using deep learning.

De novo protein design explores uncharted sequence and structure space to generate novel proteins not sampled by evolution. A main challenge in de novo design involves crafting "designable" structural templates to guide the sequence searches toward adopting target structures. We present a convolutional variational autoencoder that learns patterns of protein structure, dubbed Genesis. We coupled Genesis with trRosetta to design sequences for a set of protein folds and found that Genesis is capable of reconstructing native-like distance and angle distributions for five native folds and three novel, the so-called "dark-matter" folds as a demonstration of generalizability. We used a high-throughput assay to characterize the stability of the designs through protease resistance, obtaining encouraging success rates for folded proteins. Genesis enables exploration of the protein fold space within minutes, unrestricted by protein topologies. Our approach addresses the backbone designability problem, showing that small neural networks can efficiently learn structural patterns in proteins. A record of this paper's transparent peer review process is included in the supplemental information.

Frequency and spectrum of mutations in human sperm measured using duplex sequencing correlate with trio-based de novo mutation analyses.

De novo mutations (DNMs) are drivers of genetic disorders. However, the study of DNMs is hampered by technological limitations preventing accurate quantification of ultra-rare mutations. Duplex Sequencing (DS) theoretically has < 1 error/billion base-pairs (bp). To determine the DS utility to quantify and characterize DNMs, we analyzed DNA from blood and spermatozoa from six healthy, 18-year-old Swedish men using the TwinStrand DS mutagenesis panel (48 kb spanning 20 genic and intergenic loci). The mean single nucleotide variant mutation frequency (MF) was 1.2 × 10- 7 per bp in blood and 2.5 × 10- 8 per bp in sperm, with the most common base substitution being C > T. Blood MF and substitution spectrum were similar to those reported in blood cells with an orthogonal method. The sperm MF was in the same order of magnitude and had a strikingly similar spectrum to DNMs from publicly available whole genome sequencing data from human pedigrees (1.2 × 10- 8 per bp). DS revealed much larger numbers of insertions and deletions in sperm over blood, driven by an abundance of putative extra-chromosomal circular DNAs. The study indicates the strong potential of DS to characterize human DNMs to inform factors that contribute to disease susceptibility and heritable genetic risks.

The early hormone signaling network underlying wound-induced de novo root regeneration.

Plants possess a remarkable capability to regenerate new organs after wounding. De novo root regeneration (DNRR) from aboveground tissues after physical wounding is observed in a wide range of plant species. Here, we provide an overview of recent progress in the elucidation of the molecular mechanisms that govern DNRR, with a particular emphasis on the early signaling components. Wound-inducible chemicals and hormones such as jasmonic acid, ethylene, and salicylic acid, which were originally identified as defense hormones, influence DNRR. Overall, the ongoing elucidation of the molecular network underlying DNRR provides insight into the plant strategy of coactivating regeneration and defense responses at the early stages of the wound response.

Serum and tissue biomarkers of plasma-cell rich rejection in liver transplant recipients.

The distinction between autoimmune and alloimmune reactions in liver transplant recipients can be challenging. Plasma cell-rich rejection (PCRR), previously known as "de novo autoimmune hepatitis" or "plasma cell hepatitis", is an atypical and under-recognized form of allograft rejection observed post-liver transplantation, often in conjunction with features of T-cell-mediated and antibody-mediated rejection. If PCRR is not recognized and treated with prompt immunosuppressive augmentation, patients can develop advanced hepatic fibrosis, necro-inflammation, and allograft failure. Given the significant morbidity and mortality associated with PCRR, there exists a need to develop noninvasive biomarkers which can be used in screening, diagnosis, and treatment monitoring of PCRR. Herein is a literature review of candidate serum and tissue-based biomarkers in adult and pediatric liver transplant PCRR. We also discuss biomarkers from plasma-cell rich processes observed in other disease states and other organ transplant recipients that might be tested in liver transplant PCRR. We conclude with proposed future directions in which biomarker implementation into clinical practice could lead to advances in personalized management of PCRR.

Deep learning in template-free de novo biosynthetic pathway design of natural products.

Natural products (NPs) are indispensable in drug development, particularly in combating infections, cancer, and neurodegenerative diseases. However, their limited availability poses significant challenges. Template-free de novo biosynthetic pathway design provides a strategic solution for NP production, with deep learning standing out as a powerful tool in this domain. This review delves into state-of-the-art deep learning algorithms in NP biosynthesis pathway design. It provides an in-depth discussion of databases like Kyoto Encyclopedia of Genes and Genomes (KEGG), Reactome, and UniProt, which are essential for model training, along with chemical databases such as Reaxys, SciFinder, and PubChem for transfer learning to expand models' understanding of the broader chemical space. It evaluates the potential and challenges of sequence-to-sequence and graph-to-graph translation models for accurate single-step prediction. Additionally, it discusses search algorithms for multistep prediction and deep learning algorithms for predicting enzyme function. The review also highlights the pivotal role of deep learning in improving catalytic efficiency through enzyme engineering, which is essential for enhancing NP production. Moreover, it examines the application of large language models in pathway design, enzyme discovery, and enzyme engineering. Finally, it addresses the challenges and prospects associated with template-free approaches, offering insights into potential advancements in NP biosynthesis pathway design.

Use of sirolimus-coated balloon in de novo coronary lesions; long-term clinical outcomes from a multi-center real-world population.

BACKGROUND: Sirolimus-coated balloon (SCB), a relatively novel technology appears attractive due to the drug properties (safety and efficacy) and sirolimus remains the drug of choice in stents. However, there is limited data long-term data on SCB. In this study, we have explored the clinical outcomes following the use of SCB in de-novo lesions from a real-world practice. AIMS: To report long-term clinical outcomes following the use of Siroliumus coated balloon in de novo lesions. METHODS AND RESULTS: We analyzed all patients treated with an SCB in de novo lesions between 2016 and 2023 at four high-volume centers in UK and Italy. The outcomes measured included cardiac death, target vessel myocardial infarction (TVMI), target lesion revascularization (TLR) and major adverse cardiac events (MACE). During the study period, 771 patients had SCB in de novo lesions. Diabetes mellitus was noted in 36% of patients (n = 280), of which 14% (n = 108) were insulin dependent. Fifteen percent (n = 117) had chronic kidney disease, Fifty-two percent (n = 398) of cases were in the setting acute coronary syndrome (ACS) and of which 51 cases (7%) were ST-segment elevation myocardial infarction. Small vessels (<3.0 mm) accounted for 78% (n = 601) of cases and 76% (n = 584) were long lesions ( ≥ $\ge $ 20 mm). The mean diameter of SCB was 2.6 ± 0.4 mm and the mean length was 25 ± 10.39 mm. Bailout stenting following SCB was required in 9% lesions (n = 67). During the median follow-up 640 days, total death occurred in 39 (5%) patients and of which, cardiac death occurred in 10 patients (1.3%). TVMI occurred in 20 patients (2.6%). TLR and TVR were 5.6% and 5.8% respectively. The overall MACE rate was 8%. We had no documented case of acute vessel closure. CONCLUSIONS: The results from this long-term follow-up in a real-world population are encouraging with low rates of hard endpoints and acceptable rates of TLR and MACE despite a complex group of patients. Our data suggest that SCBs are safe in coronary intervention with good clinical outcomes in the long term.

Olverembatinib treatment in adult patients with newly diagnosed Philadelphia chromosome-positive acute lymphoblastic leukemia.

Olverembatinib is a novel orally administered third-generation tyrosine kinase inhibitor (TKI) with definitive responses in T315I-mutant chronic myeloid leukemia (CML) patients. However, its value in newly diagnosed Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph + ALL) remained unclarified. In this multiple-center study, 20 patients with de novo Ph + ALL were treated with olverembatinib-based regimens as frontline therapy. All patients acquired complete remission (CR) after induction. 85% of patients achieved complete molecular response (CMR) within three months, contributed mainly by the addition of blinatumomab. A total of 45% of patients experienced mild hematological treatment-related adverse events (TRAEs). Olverembatinib-based treatment led to promising outcomes in de novo Ph + ALL patients but warranted further studies to investigate the best-combined strategy.

Establishing M1 subdivision for de novo nasopharyngeal carcinoma patients receiving immuno-chemotherapy: A multicenter, retrospective cohort study.

OBJECTIVES: This study aims to better manage de novo metastatic nasopharyngeal carcinoma (NPC) patients receiving palliative immuno-chemotherapy (PICT), thereby easily determining individual survival outcomes. MATERIALS AND METHODS: Patients with de novo metastatic NPC from four centers who received first-line PICT were included. We developed a nomogram for the pretherapy overall survival (OS) prediction using a logistic regression model in the training cohort (n = 296). We assessed the performance of this nomogram in a validation cohort. RESULTS: A total of 592 patients were included. The median follow-up time was 29.83 months. Bone metastasis (HR, 2.46; 95 % CI, 1.01-6.21; p = 0.049) and the number of metastatic lesions > 3 (HR, 2.78; 95 % CI, 1.24-6.24; p = 0.013) were independent prognostic indicators. A new two-category M1 subdivision was generated: M1a, defined by the absence of co-existing bone metastasis and the presence of more than three metastatic lesions; and M1b, characterized by the presence of co-existing bone metastasis and the presence of more than three metastatic lesions. The 3-year OS rates of patients with M1a vs. M1b were 87.1 % vs. 60.3 % (p < 0.001). The C-indexes were 0.652 and 0.581 in the training and validation cohorts. The 1-, 2-, and 3-year areas under the curve (AUC) were 0.69, 0.68, 0.68 in the training cohort and 0.64, 0.6, 0.6 in the validation cohort. DCA curves also indicated that the nomogram has good clinical utility. CONCLUSION: The proposed M1 subdivision provides good OS segregation for patients receiving PICT.

Intracoronary thrombolysis combined with drug balloon angioplasty in a young ST-segment elevation myocardial infarction patient: A case report.

BACKGROUND: The combination of acute ST-segment elevation myocardial infarction (STEMI) and gastric ulcers poses a challenge to primary percutaneous coronary intervention (PPCI), particularly for young patients. The role of drug-coated balloons (DCBs) in the treatment of de novo coronary artery lesions in large vessels remains unclear, especially for patients with STEMI. Our strategy is to implement drug balloon angioplasty following the intracoronary administration of low-dose prourokinase and adequate pre-expansion. CASE SUMMARY: A 54-year-old male patient presented to the emergency department due to chest pain on June 24, 2019. Within the first 3 minutes of the initial assessment in the emergency room, the electrocardiogram (ECG) showed significant changes. There was atrial fibrillation with ST-segment elevation. Subsequently, atrial fibrillation terminated spontaneously and reverted to sinus rhythm. Soon after, the patient experienced syncope. The ECG revealed torsades de pointes ventricular tachycardia. A few seconds later, it returned to sinus rhythm. High-sensitivity tropon in I was normal. The diagnosis was acute STEMI. Emergency coronary angiography revealed subtotal occlusion with thrombus formation in the proximal segment of the left anterior descending artery. Considering the patient's age and history of peptic ulcer disease, after the intracoronary injection of prourokinase, percutaneous transluminal coronary angioplasty and cutting balloon angioplasty were conducted for thorough preconditioning, and paclitaxel drug-eluting balloon angioplasty was performed without any stents, achieving favorable outcomes. CONCLUSION: A PPCI without stents may be a viable treatment strategy for select patients with STEMI, and further research is warranted.

Survival outcomes in patients with de novo metastatic Merkel cell carcinoma according to site of metastases.

Introduction: Merkel cell carcinoma (MCC) is a rare and aggressive neuroendocrine malignancy of the skin with a predilection for metastases. This study investigates the clinical outcomes in patients presenting with de novo Stage IV MCC according to the metastatic site(s) at presentation. Materials and methods: Patients who presented with one or more sites of distant metastatic MCC at initial diagnosis between 2009 and 2023 were identified. The presence or absence of one or more metastases in each organ was categorized for each patient at the time of diagnosis. Overall survival (OS) and progression-free survival (PFS) were estimated using the Kaplan-Meier method. Competing risk analysis was used to estimate the cumulative occurrence risk of MCC-specific death. Fisher's exact test was used for response rate analysis. Results were considered statically significant if p < 0.05. Results: Thirty-four patients presented with de novo distant metastatic MCC. There was no association between the number of metastatic sites at diagnosis and OS (p= 0.58), PFS (p=0.79), or response rates (p=0.53). However, the presence of bone metastases was associated with significantly shorter OS (8.2 versus 25.2 months, HR: 2.4, 95% CI 1.01-5.7, p= 0.04). MCC-specific death in patients with lymph node metastases was significantly lower than in patients without (HR: 0.28, 95% CI: 0.09-0.87, p= 0.013). The presence of bone metastases tended to associate with an increased risk of MCC-specific death, although not statistically significant. The location of metastases was not associated with the response rate to first-line treatment. There was no significant association between site of metastases and PFS. Conclusion: In this cohort of patients with de novo metastatic MCC, the presence of bone metastases, but not the number of organs involved, was associated with significantly worse OS. The presence of lymph node metastases was associated with lower MCC-specific death. Further research is warranted in larger cohorts to investigate the impact of the location of metastases on clinical outcomes.

Dissociation between liver fat content and fasting metabolic markers of selective hepatic insulin resistance in humans.

OBJECTIVE: Fasting hyperglycemia and hypertriglyceridemia are characteristic of insulin resistance (IR) and rodent work has suggested this may be due to selective hepatic IR; defined by increased hepatic gluconeogenesis and de novo lipogenesis (DNL), but this has not been shown in humans. DESIGN: Cross-sectional study in men and women across a range of adiposity. METHODS: Medication-free participants (n=177) were classified as normoinsulinemic (NI) or hyperinsulinemic (HI) and as having low (LF) or high (HF) liver fat content measured by magnetic resonance spectroscopy. Fractional gluconeogenesis (frGNG) and hepatic DNL were measured using stable isotope tracer methodology following an overnight fast. RESULTS: Although HI and HF groups had higher fasting plasma glucose and triglyceride concentrations when compared to NI and LF groups respectively, there was no difference in frGNG. However, HF participants tended to have lower frGNG than LF participants. HI participants had higher DNL compared to NI participants but there was no difference observed between liver fat groups. CONCLUSIONS: Taken together, we found no metabolic signature of selective hepatic IR in fasting humans. DNL may contribute to hypertriglyceridemia in individuals with HI but not those with HF. Glycogenolysis and systemic glucose clearance may have a larger contribution to fasting hyperglycemia than gluconeogenesis, especially in those with HF and these pathways should be considered for therapeutic targeting.