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Despite the low incidence of primary cardiac tumors, recently at our institution, we have experienced two very rare tumors in the span of just a few months. Hibernomas are rare tumors of brown adipose tissue origin that share the benign clinical features of a lipoma, but on imaging mimic the more aggressive sarcoma. Here we present two separate cases of otherwise healthy patients who were found incidentally to have these asymptomatic tumors.
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Serum ferritin concentrations increase during hepatic inflammation and correlate with the severity of chronic liver disease. Here, we report a molecular mechanism whereby the heavy subunit of ferritin (FTH) contributes to hepatic inflammation. We found that FTH induced activation of the NLRP3 inflammasome and secretion of the proinflammatory cytokine interleukin-1ß (IL-1ß) in primary rat hepatic stellate cells (HSCs) through intercellular adhesion molecule-1 (ICAM-1). FTH-ICAM-1 stimulated the expression of Il1b, NLRP3 inflammasome activation, and the processing and secretion of IL-1ß in a manner that depended on plasma membrane remodeling, clathrin-mediated endocytosis, and lysosomal destabilization. FTH-ICAM-1 signaling at early endosomes stimulated Il1b expression, implying that this endosomal signaling primed inflammasome activation in HSCs. In contrast, lysosomal destabilization was required for FTH-induced IL-1ß secretion, suggesting that lysosomal damage activated inflammasomes. FTH induced IL-1ß production in liver slices from wild-type mice but not in those from Icam1-/- or Nlrp3-/- mice. Thus, FTH signals through its receptor ICAM-1 on HSCs to activate the NLRP3 inflammasome. We speculate that this pathway contributes to hepatic inflammation, a key process that stimulates hepatic fibrogenesis associated with chronic liver disease.
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Inflamasomas , Hepatopatías , Ratas , Ratones , Animales , Inflamasomas/genética , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Molécula 1 de Adhesión Intercelular/genética , Molécula 1 de Adhesión Intercelular/metabolismo , Células Estrelladas Hepáticas/metabolismo , Ferritinas/genética , Ferritinas/metabolismo , Interleucina-1beta/metabolismo , Inflamación/genética , Inflamación/metabolismoRESUMEN
We describe the case of a 55-year-old man with a pseudocoarctation of the descending aorta following a conventional elephant trunk technique. The patient underwent aortic arch replacement with the conventional elephant trunk technique. After the operation, he had developed an increasing creatinine level, hemolysis, and cyanosis of his toes. Femoral arterial line placement confirmed a 50-mm Hg systolic pressure gradient between his radial and femoral arteries. Computed tomography angiography revealed that the elephant trunk graft within the true lumen was compressed, resulting in a pseudocoarctation. The patient was successfully treated with thoracic endovascular aneurysm repair.
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A 43-year-old man presented with a several-month history of worsening left shoulder pain. On imaging, he was found to have an osseous mass arising from his left second rib and protruding into the soft tissues of his chest. The mass had radiographic characteristics consistent with those of an osteochondroma. He had point tenderness over the mass, and the area of point tenderness was consistent with his description of the location of his pain over the past several months. Based on his symptoms, he was taken to the operating room for robotic excision of this mass. He was placed in a right lateral decubitus position, and three robotic ports were inserted. The mass was identified based on landmarks and was dissected free. The bony attachment of the mass to the second rib was transected using a Kerrison rongeur. The mass was delivered into the chest and removed using an endobag. The patient was discharged the following day after removal of his Blake drain. His pain had completely resolved at the postoperative follow-up examination, and his final pathological report confirmed the benign diagnosis of osteochondroma.
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Osteocondroma , Procedimientos Quirúrgicos Robotizados , Masculino , Humanos , Adulto , Costillas/cirugía , Osteocondroma/cirugía , Osteocondroma/patología , DolorRESUMEN
Snake venoms constitute a complex, rapidly evolving trait, whose composition varies between and within populations depending on geographical location, age and preys (diets). These factors have determined the adaptive evolution for predatory success and link venom heterogeneity with prey specificity. Moreover, understanding the evolutionary drivers of animal venoms has streamlined the biodiscovery of venom-derived compounds as drug candidates in biomedicine and biotechnology. The king cobra (Ophiophagus hannah; Cantor, 1836) is distributed in diverse habitats, forming independent populations, which confer differing scale markings, including between hatchlings and adults. Furthermore, king cobra venoms possess unique cytotoxic properties that are used as a defensive trait, but their toxins may also have utility as promising anticancer-agent candidates. However, the impact of geographical distribution and age on these potential venom applications has been typically neglected. In this study, we hypothesised that ontogenetic venom variation accompanies the morphological distinction between hatchlings and adults. We used non-transformed neonatal foreskin (NFF) fibroblasts to examine and compare the variability of venom cytotoxicity between adult captive breeding pairs from Malaysian and Chinese lineages, along with that of their progeny upon hatching. In parallel, we assessed the anticancer potential of these venoms in human-melanoma-patient-derived cells (MM96L). We found that in a geographical distribution and gender-independent manner, venoms from hatchlings were significantly less cytotoxic than those from adults (NFF; ~Log EC50: 0.5-0.6 vs. 0.2-0.35 mg/mL). This is consistent with neonates occupying a semifossorial habitat, while adults inhabit more above-ground habitats and are therefore more conspicuous to potential predators. We also observed that Malaysian venoms exhibited a slightly higher cytotoxicity than those from the Chinese cobra cohorts (NFF; Log EC50: 0.1-0.3 vs. 0.3-0.4 mg/mL), which is consistent with Malaysian king cobras being more strongly aposematically marked. These variations are therefore suggestive of differential anti-predator strategies associated with the occupation of distinct niches. However, all cobra venoms were similarly cytotoxic in both melanoma cells and fibroblasts, limiting their potential medical applications in their native forms.
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Venenos Elapídicos , Fibroblastos , Melanoma , Adulto , Animales , Humanos , Recién Nacido , Masculino , Prepucio/citología , Geografía , Melanoma/tratamiento farmacológico , Ophiophagus hannah , Fibroblastos/efectos de los fármacosRESUMEN
Following on from the NASA twins' study, there has been a tremendous interest in the use of omics techniques in spaceflight. Individual space agencies, NASA's GeneLab, JAXA's ibSLS, and the ESA-funded Space Omics Topical Team and the International Standards for Space Omics Processing (ISSOP) groups have established several initiatives to support this growth. Here, we present recommendations from the Space Omics Topical Team to promote standard application of space omics in Europe. We focus on four main themes: i) continued participation in and coordination with international omics endeavors, ii) strengthening of the European space omics infrastructure including workforce and facilities, iii) capitalizing on the emerging opportunities in the commercial space sector, and iv) capitalizing on the emerging opportunities in human subjects research.
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The liver is the only solid organ capable of regenerating itself to regain 100% of its mass and function after liver injury and/or partial hepatectomy (PH). This exceptional property represents a therapeutic opportunity for severe liver disease patients. However, liver regeneration (LR) might fail due to poorly understood causes. Here, we have investigated the regulation of liver proteome and phosphoproteome at a short time after PH (9 h), to depict a detailed mechanistic background of the early LR phase. Furthermore, we analyzed the dynamic changes of the serum proteome and metabolome of healthy living donor liver transplant (LDLT) donors at different time points after surgery. The molecular profiles from both analyses were then correlated. Insulin and FXR-FGF15/19 signaling were stimulated in mouse liver after PH, leading to the activation of the main intermediary kinases (AKT and ERK). Besides, inhibition of the hippo pathway led to an increased expression of its target genes and of one of its intermediary proteins (14-3-3 protein), contributing to cell proliferation. In association with these processes, metabolic reprogramming coupled to enhanced mitochondrial activity cope for the energy and biosynthetic requirements of LR. In human serum of LDLT donors, we identified 56 proteins and 13 metabolites statistically differential which recapitulate some of the main cellular processes orchestrating LR in its early phase. These results provide mechanisms and protein mediators of LR that might prove useful for the follow-up of the regenerative process in the liver after PH as well as preventing the occurrence of complications associated with liver resection.
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Regeneración Hepática , Trasplante de Hígado , Ratones , Animales , Humanos , Regeneración Hepática/genética , Trasplante de Hígado/métodos , Proteoma/genética , Proteoma/metabolismo , Donadores Vivos , Hígado/cirugía , Hígado/metabolismoRESUMEN
Objective: To evaluate a novel technology for real time tracking of RF-Identified (RFID) surgical tools (Biotic System), providing intraoperative data analytics during simulated cardiovascular procedures. Ineffective asset management in the Operating Room (OR) leads to inefficient utilization of resources and contributes to prolonged operative times and increased costs. Analysis of captured data can assist in quantifying instrument utilization, procedure flow, performance and prevention of retained instruments. Methods & Results: Five surgeons performed thirteen simulated surgical cases on three human cadavers. Procedures included (i) two abdominal aortic aneurysm (AAA) repairs, (ii) three carotid endarterectomies (CE), (iii) two femoropopliteal (fem-pop) bypasses, (iv) thoracic aortic aneurysm repair, (v) coronary artery bypass graft, (vi) aortic valve replacement, (vii) ascending aortic aneurysm repair, (viii) heart transplants, and (ix) mitral valve replacement. For each case an average of 139 surgical instruments were RFID-tagged and tracked intraoperatively. Data was captured and analyzed retrospectively. Of the 139 instruments tracked across each of the 13 cases, 55 instruments (39.5%) were actually used, demonstrating a high level of redundancy. For repeat cases (i.e. CE/AAA/fem-pop): (i) average instrument usage was 41 ± 3.6 (8.8% variation) for CE (n=3); (ii) average instrument usage was 69 ± 4.0 (5.8% variation) for AAA (n=2); and (iii) average instrument usage was 48 ± 2.5 (5.3% variation) for fem- pop (n=2). Results also showed a reduction in end-of-procedure instrument counting times of 58-87%. Conclusions: We report on a method for collecting intraoperative data analytics regarding instrument usage via RFID technology. This system will help refine instrument selection, quantitate instrument utilization and prevent inadvertent retention in a patient. This should help increase efficiency in packaging and sterilization and let surgeons make objective decisions in the composition of surgical trays. Clinical and Translational Impact Statement-Intraoperative analytics of surgical tools and associated equipment may ultimately lead to safer more efficient surgeries that increase patient outcomes while decreasing the cost of care.
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Aneurisma de la Aorta Abdominal , Dispositivo de Identificación por Radiofrecuencia , Aneurisma de la Aorta Abdominal/cirugía , Humanos , Quirófanos , Dispositivo de Identificación por Radiofrecuencia/métodos , Estudios Retrospectivos , Instrumentos QuirúrgicosRESUMEN
YAP1 and TAZ are transcriptional co-activator proteins that play fundamental roles in many biological processes, from cell proliferation and cell lineage fate determination to tumorigenesis. We previously demonstrated that Limb Expression 1 (LIX1) regulates YAP1 and TAZ activity and controls digestive mesenchymal progenitor proliferation. However, LIX1 mode of action remains elusive. Here, we found that endogenous LIX1 is localized in mitochondria and is anchored to the outer mitochondrial membrane through S-palmitoylation of cysteine 84, a residue conserved in all LIX1 orthologs. LIX1 downregulation altered the mitochondrial ultrastructure, resulting in a significantly decreased respiration and attenuated production of mitochondrial reactive oxygen species (mtROS). Mechanistically, LIX1 knock-down impaired the stability of the mitochondrial proteins PHB2 and OPA1 that are found in complexes with mitochondrial-specific phospholipids and are required for cristae organization. Supplementation with unsaturated fatty acids counteracted the effects of LIX1 knock-down on mitochondrial morphology and ultrastructure and restored YAP1/TAZ signaling. Collectively, our data demonstrate that LIX1 is a key regulator of cristae organization, modulating mtROS level and subsequently regulating the signaling cascades that control fate commitment of digestive mesenchyme-derived cells.
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Cisteína , Mitocondrias , Cisteína/metabolismo , Mesodermo/metabolismo , Mitocondrias/metabolismo , Proteínas Mitocondriales/metabolismo , Fosfolípidos/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
BACKGROUND AND PURPOSE: Over past decades, targeted therapies and immunotherapy have improved survival and reduced the morbidity of patients with BRAF-mutated melanoma. However, drug resistance and relapse hinder overall success. Therefore, there is an urgent need for novel compounds with therapeutic efficacy against BRAF-melanoma. This prompted us to investigate the antiproliferative profile of a tachykinin-peptide from the Octopus kaurna, Octpep-1 in melanoma. EXPERIMENTAL APPROACH: We evaluated the cytotoxicity of Octpep-1 by MTT assay. Mechanistic insights on viability and cellular damage caused by Octpep-1 were gained via flow cytometry and bioenergetics. Structural and pharmacological characterization was conducted by molecular modelling, molecular biology, CRISPR/Cas9 technology, high-throughput mRNA and calcium flux analysis. In vivo efficacy was validated in two independent xerograph animal models (mice and zebrafish). KEY RESULTS: Octpep-1 selectively reduced the proliferative capacity of human melanoma BRAFV600E -mutated cells with minimal effects on fibroblasts. In melanoma-treated cells, Octpep-1 increased ROS with unaltered mitochondrial membrane potential and promoted non-mitochondrial and mitochondrial respiration with inefficient ATP coupling. Molecular modelling revealed that the cytotoxicity of Octpep-1 depends upon the α-helix and polyproline conformation in the C-terminal region of the peptide. A truncated form of the C-terminal end of Octpep-1 displayed enhanced potency and efficacy against melanoma. Octpep-1 reduced the progression of tumours in xenograft melanoma mice and zebrafish. CONCLUSION AND IMPLICATIONS: We unravel the intrinsic anti-tumoural properties of a tachykinin peptide. This peptide mediates the selective cytotoxicity in BRAF-mutated melanoma in vitro and prevents tumour progression in vivo, providing a foundation for a therapy against melanoma.
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Antineoplásicos , Melanoma , Adenosina Trifosfato , Animales , Antineoplásicos/farmacología , Calcio , Línea Celular Tumoral , Humanos , Melanoma/tratamiento farmacológico , Melanoma/patología , Ratones , Mutación , Octopodiformes/química , Péptidos/farmacología , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas B-raf/uso terapéutico , ARN Mensajero , Especies Reactivas de Oxígeno , Taquicininas/genética , Taquicininas/uso terapéutico , Pez Cebra/genéticaRESUMEN
Devil facial tumor disease (DFTD) and its lack of available therapies are propelling the Tasmanian devil population toward extinction. This study demonstrates that cholesterol homeostasis and carbohydrate energy metabolism sustain the proliferation of DFTD cells in a cell-type-dependent manner. In addition, we show that the liver-X nuclear receptor-ß (LXRß), a major cholesterol cellular sensor, and its natural ligand 24S-hydroxycholesterol promote the proliferation of DFTD cells via a metabolic switch toward aerobic glycolysis. As a proof of concept of the role of cholesterol homeostasis on DFTD proliferation, we show that atorvastatin, an FDA-approved statin-drug subtype used against human cardiovascular diseases that inhibits cholesterol synthesis, shuts down DFTD energy metabolism and prevents tumor growth in an in vivo DFTD-xenograft model. In conclusion, we show that intervention against cholesterol homeostasis and carbohydrate-dependent energy metabolism by atorvastatin constitutes a feasible biochemical treatment against DFTD, which may assist in the conservation of the Tasmanian devil.
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Colesterol/metabolismo , Neoplasias Faciales/metabolismo , Neoplasias Faciales/veterinaria , Homeostasis , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Receptores X del Hígado/metabolismo , Marsupiales/metabolismo , Aerobiosis/efectos de los fármacos , Animales , Atorvastatina/farmacología , Proliferación Celular/efectos de los fármacos , Neoplasias Faciales/patología , Femenino , Glucólisis/efectos de los fármacos , Humanos , Ratones Endogámicos BALB C , Ratones Desnudos , Oxiesteroles/farmacología , Transducción de Señal/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Melanoma is the main cause of skin cancer deaths, with special emphasis in those cases carrying BRAF mutations that trigger the mitogen-activated protein kinases (MAPK) signaling and unrestrained cell proliferation in the absence of mitogens. Current therapies targeting MAPK are hindered by drug resistance and relapse that rely on metabolic rewiring and Akt activation. To identify new drug candidates against melanoma, we investigated the molecular mechanism of action of the Octopus Kaurna-derived peptide, Octpep-1, in human BRAF(V600E) melanoma cells using proteomics and RNAseq coupled with metabolic analysis. Fluorescence microscopy verified that Octpep-1 tagged with fluorescein enters MM96L and NFF cells and distributes preferentially in the perinuclear area of MM96L cells. Proteomics and RNAseq revealed that Octpep-1 targets PI3K/AKT/mTOR signaling in MM96L cells. In addition, Octpep-1 combined with rapamycin (mTORC1 inhibitor) or LY3214996 (ERK1/2 inhibitor) augmented the cytotoxicity against BRAF(V600E) melanoma cells in comparison with the inhibitors or Octpep-1 alone. Octpep-1-treated MM96L cells displayed reduced glycolysis and mitochondrial respiration when combined with LY3214996. Altogether these data support Octpep-1 as an optimal candidate in combination therapies for melanoma BRAF(V600E) mutations.
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Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Diana Mecanicista del Complejo 1 de la Rapamicina/antagonistas & inhibidores , Melanoma/tratamiento farmacológico , Mutación , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas B-raf/genética , Sirolimus/farmacología , Neoplasias Cutáneas/tratamiento farmacológico , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Metabolismo Energético/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Humanos , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Melanoma/enzimología , Melanoma/genética , Melanoma/patología , Transducción de Señal , Neoplasias Cutáneas/enzimología , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patologíaRESUMEN
Excessive consumption of high-fructose diets is associated with insulin resistance, obesity, and non-alcoholic fatty liver disease (NAFLD). However, fructose differentially affects hepatic regulation of lipogenesis in males and females. Hence, additional studies are necessary in order to find strategies taking gender disparities in fructose-induced liver damage into consideration. Although the eighth member of facilitated glucose transporters (GLUT8) has been linked to fructose-induced macrosteatosis in female mice, its contribution to the inflammatory state of NAFLD remains to be elucidated. Combining pharmacological, biochemical, and proteomic approaches, we evaluated the preventive effect of targeted liver GLUT8 silencing on liver injury in a mice female fructose-induced non-alcoholic steatohepatitis female mouse model. Liver GLUT8-knockdown attenuated fructose-induced ER stress, recovered liver inflammation, and dramatically reduced fatty acid content, in part, via the omega oxidation. Therefore, this study links GLUT8 with liver inflammatory response and suggests GLUT8 as a potential target for the prevention of NAFLD.
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Snakes of the genera Pseudocerastes and Eristicophis (Viperidae: Viperinae) are known as the desert vipers due to their association with the arid environments of the Middle East. These species have received limited research attention and little is known about their venom or ecology. In this study, a comprehensive analysis of desert viper venoms was conducted by visualising the venom proteomes via gel electrophoresis and assessing the crude venoms for their cytotoxic, haemotoxic, and neurotoxic properties. Plasmas sourced from human, toad, and chicken were used as models to assess possible prey-linked venom activity. The venoms demonstrated substantial divergence in composition and bioactivity across all experiments. Pseudocerastes urarachnoides venom activated human coagulation factors X and prothrombin and demonstrated potent procoagulant activity in human, toad, and chicken plasmas, in stark contrast to the potent neurotoxic venom of P. fieldi. The venom of E. macmahonii also induced coagulation, though this did not appear to be via the activation of factor X or prothrombin. The coagulant properties of P. fieldi and P. persicus venoms varied among plasmas, demonstrating strong anticoagulant activity in the amphibian and human plasmas but no significant effect in that of bird. This is conjectured to reflect prey-specific toxin activity, though further ecological studies are required to confirm any dietary associations. This study reinforces the notion that phylogenetic relatedness of snakes cannot readily predict venom protein composition or function. The significant venom variation between these species raises serious concerns regarding antivenom paraspecificity. Future assessment of antivenom is crucial.
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Coagulación Sanguínea/efectos de los fármacos , Unión Neuromuscular/efectos de los fármacos , Conducta Predatoria , Proteínas de Reptiles/toxicidad , Mordeduras de Serpientes/metabolismo , Ponzoñas/toxicidad , Viperidae/metabolismo , Animales , Anuros , Línea Celular Tumoral , Pollos , Humanos , Masculino , Unión Neuromuscular/fisiopatología , Proteoma , Proteómica , Proteínas de Reptiles/metabolismo , Mordeduras de Serpientes/sangre , Mordeduras de Serpientes/fisiopatología , Especificidad de la Especie , Ponzoñas/metabolismoRESUMEN
BACKGROUND AND AIMS: Growth hormone (GH) is important for liver regeneration after partial hepatectomy (PHx). We investigated this process in C57BL/6 mice that express different forms of the GH receptor (GHR) with deletions in key signaling domains. APPROACH AND RESULTS: PHx was performed on C57BL/6 mice lacking GHR (Ghr-/- ), disabled for all GH-dependent Janus kinase 2 signaling (Box1-/- ), or lacking only GH-dependent signal transducer and activator of transcription 5 (STAT5) signaling (Ghr391-/- ), and wild-type littermates. C57BL/6 Ghr-/- mice showed striking mortality within 48 hours after PHx, whereas Box1-/- or Ghr391-/- mice survived with normal liver regeneration. Ghr-/- mortality was associated with increased apoptosis and elevated natural killer/natural killer T cell and macrophage cell markers. We identified H2-Bl, a key immunotolerance protein, which is up-regulated by PHx through a GH-mediated, Janus kinase 2-independent, SRC family kinase-dependent pathway. GH treatment was confirmed to up-regulate expression of the human homolog of H2-Bl (human leukocyte antigen G [HLA-G]) in primary human hepatocytes and in the serum of GH-deficient patients. We find that injury-associated innate immune attack by natural killer/natural killer T cell and macrophage cells are instrumental in the failure of liver regeneration, and this can be overcome in Ghr-/- mice by adenoviral delivery of H2-Bl or by infusion of HLA-G protein. Further, H2-Bl knockdown in wild-type C57BL/6 mice showed elevated markers of inflammation after PHx, whereas Ghr-/- backcrossed on a strain with high endogenous H2-Bl expression showed a high rate of survival following PHx. CONCLUSIONS: GH induction of H2-Bl expression is crucial for reducing innate immune-mediated apoptosis and promoting survival after PHx in C57BL/6 mice. Treatment with HLA-G may lead to improved clinical outcomes following liver surgery or transplantation.
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Hormona del Crecimiento/deficiencia , Antígenos H-2/metabolismo , Antígenos HLA-G/metabolismo , Regeneración Hepática/inmunología , Hígado/fisiología , Animales , Apoptosis/inmunología , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Células Cultivadas , Técnicas de Cocultivo , Técnicas de Silenciamiento del Gen , Antígenos H-2/genética , Antígenos HLA-G/genética , Antígenos HLA-G/aislamiento & purificación , Hepatectomía , Hepatocitos , Humanos , Inmunidad Innata , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/metabolismo , Hígado/cirugía , Macrófagos/inmunología , Macrófagos/metabolismo , Ratones , Células T Asesinas Naturales/inmunología , Células T Asesinas Naturales/metabolismo , Cultivo Primario de Células , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/metabolismo , Transducción de Señal/genética , Transducción de Señal/inmunologíaRESUMEN
Mitochondrial ATP-synthesis is catalyzed by a F1Fo-ATP synthase, an enzyme of dual genetic origin enriched at the edge of cristae where it plays a key role in their structure/stability. The enzyme's biogenesis remains poorly understood, both from a mechanistic and a compartmentalization point of view. The present study provides novel molecular insights into this process through investigations on a human protein called TMEM70 with an unclear role in the assembly of ATP synthase. A recent study has revealed the existence of physical interactions between TMEM70 and the subunit c (Su.c), a protein present in 8 identical copies forming a transmembrane oligomeric ring (c-ring) within the ATP synthase proton translocating domain (Fo). Herein we analyzed the ATP-synthase assembly in cells lacking TMEM70, mitochondrial DNA or F1 subunits and observe a direct correlation between TMEM70 and Su.c levels, regardless of the status of other ATP synthase subunits or of mitochondrial bioenergetics. Immunoprecipitation, two-dimensional blue-native/SDS-PAGE, and pulse-chase experiments reveal that TMEM70 forms large oligomers that interact with Su.c not yet incorporated into ATP synthase complexes. Moreover, discrete TMEM70-Su.c complexes with increasing Su.c contents can be detected, suggesting a role for TMEM70 oligomers in the gradual assembly of the c-ring. Furthermore, we demonstrate using expansion super-resolution microscopy the specific localization of TMEM70 at the inner cristae membrane, distinct from the MICOS component MIC60. Taken together, our results show that TMEM70 oligomers provide a scaffold for c-ring assembly and that mammalian ATP synthase is assembled within inner cristae membranes.
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Proteínas de la Membrana/química , Proteínas de la Membrana/metabolismo , Proteínas Mitocondriales/química , Proteínas Mitocondriales/metabolismo , ATPasas de Translocación de Protón Mitocondriales/química , ATPasas de Translocación de Protón Mitocondriales/metabolismo , Línea Celular , Metabolismo Energético , Técnicas de Inactivación de Genes , Células HEK293 , Humanos , Proteínas de la Membrana/genética , Microscopía Electrónica , Membranas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética , Dominios Proteicos , Multimerización de ProteínaRESUMEN
Surgical site infection (SSIs) in lower extremity vascular procedures is a major contributor to patient morbidity and mortality. Despite previous advancements in preoperative and postoperative care, the surgical infection rate in vascular surgery remains high, particularly when groin incisions are involved. However, successfully targeting modifiable risk factors reduces the surgical site infection incidence in vascular surgery patients. We conducted an extensive literature review to evaluate the efficacy of various preventive strategies for groin surgical site infections. We discuss the role of preoperative showers, preoperative and postoperative antibiotics, collagen gentamicin implants, iodine impregnated drapes, types of skin incisions, negative pressure wound therapy, and prophylactic muscle flap transposition in preventing surgical site infection in the groin after vascular surgical procedures.
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Ingle/irrigación sanguínea , Infección de la Herida Quirúrgica/prevención & control , Procedimientos Quirúrgicos Vasculares/efectos adversos , Humanos , Medición de Riesgo , Factores de Riesgo , Infección de la Herida Quirúrgica/diagnóstico , Infección de la Herida Quirúrgica/microbiología , Resultado del TratamientoRESUMEN
Since its discovery twenty-five years ago, the fat-derived hormone leptin has provided a revolutionary framework for studying the physiological role of adipose tissue as an endocrine organ. Leptin exerts pleiotropic effects on many metabolic pathways and is tightly connected with the liver, the major player in systemic metabolism. As a consequence, understanding the metabolic and hormonal interplay between the liver and adipose tissue could provide us with new therapeutic targets for some chronic liver diseases, an increasing problem worldwide. In this review, we assess relevant literature regarding the main metabolic effects of leptin on the liver, by direct regulation or through the central nervous system (CNS). We draw special attention to the contribution of leptin to the non-alcoholic fatty liver disease (NAFLD) pathogenesis and its progression to more advanced stages of the disease as non-alcoholic steatohepatitis (NASH). Likewise, we describe the contribution of leptin to the liver regeneration process after partial hepatectomy, the mainstay of treatment for certain hepatic malignant tumors.