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1.
Nature ; 628(8009): 752-757, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38622268

RESUMO

In recent years, the stacking and twisting of atom-thin structures with matching crystal symmetry has provided a unique way to create new superlattice structures in which new properties emerge1,2. In parallel, control over the temporal characteristics of strong light fields has allowed researchers to manipulate coherent electron transport in such atom-thin structures on sublaser-cycle timescales3,4. Here we demonstrate a tailored light-wave-driven analogue to twisted layer stacking. Tailoring the spatial symmetry of the light waveform to that of the lattice of a hexagonal boron nitride monolayer and then twisting this waveform result in optical control of time-reversal symmetry breaking5 and the realization of the topological Haldane model6 in a laser-dressed two-dimensional insulating crystal. Further, the parameters of the effective Haldane-type Hamiltonian can be controlled by rotating the light waveform, thus enabling ultrafast switching between band structure configurations and allowing unprecedented control over the magnitude, location and curvature of the bandgap. This results in an asymmetric population between complementary quantum valleys that leads to a measurable valley Hall current7, which can be detected by optical harmonic polarimetry. The universality and robustness of our scheme paves the way to valley-selective bandgap engineering on the fly and unlocks the possibility of creating few-femtosecond switches with quantum degrees of freedom.

2.
Nature ; 628(8009): 746-751, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38658682

RESUMO

The valley degree of freedom1-4 of electrons in materials promises routes towards energy-efficient information storage with enticing prospects for quantum information processing5-7. Current challenges in utilizing valley polarization are symmetry conditions that require monolayer structures8,9 or specific material engineering10-13, non-resonant optical control to avoid energy dissipation and the ability to switch valley polarization at optical speed. We demonstrate all-optical and non-resonant control over valley polarization using bulk MoS2, a centrosymmetric material without Berry curvature at the valleys. Our universal method utilizes spin angular momentum-shaped trefoil optical control pulses14,15 to switch the material's electronic topology and induce valley polarization by transiently breaking time and space inversion symmetry16 through a simple phase rotation. We confirm valley polarization through the transient generation of the second harmonic of a non-collinear optical probe pulse, depending on the trefoil phase rotation. The investigation shows that direct optical control over the valley degree of freedom is not limited to monolayer structures. Indeed, such control is possible for systems with an arbitrary number of layers and for bulk materials. Non-resonant valley control is universal and, at optical speeds, unlocks the possibility of engineering efficient multimaterial valleytronic devices operating on quantum coherent timescales.

3.
Nature ; 626(7997): 66-71, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38233521

RESUMO

Ever since its discovery1, the notion of the Berry phase has permeated all branches of physics and plays an important part in a variety of quantum phenomena2. However, so far all its realizations have been based on a continuous evolution of the quantum state, following a cyclic path. Here we introduce and demonstrate a conceptually new manifestation of the Berry phase in light-driven crystals, in which the electronic wavefunction accumulates a geometric phase during a discrete evolution between different bands, while preserving the coherence of the process. We experimentally reveal this phase by using a strong laser field to engineer an internal interferometer, induced during less than one cycle of the driving field, which maps the phase onto the emission of higher-order harmonics. Our work provides an opportunity for the study of geometric phases, leading to a variety of observations in light-driven topological phenomena and attosecond solid-state physics.

4.
Gastroenterology ; 165(1): 187-200.e7, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36966941

RESUMO

BACKGROUND & AIMS: Excess copper causes hepatocyte death in hereditary Wilson's disease (WD). Current WD treatments by copper-binding chelators may gradually reduce copper overload; they fail, however, to bring hepatic copper close to normal physiological levels. Consequently, lifelong daily dose regimens are required to hinder disease progression. This may result in severe issues due to nonadherence or unwanted adverse drug reactions and also due to drug switching and ultimate treatment failures. This study comparatively tested bacteria-derived copper binding agents-methanobactins (MBs)-for efficient liver copper depletion in WD rats as well as their safety and effect duration. METHODS: Copper chelators were tested in vitro and in vivo in WD rats. Metabolic cage housing allowed the accurate assessment of animal copper balances and long-term experiments related to the determination of minimal treatment phases. RESULTS: We found that copper-binding ARBM101 (previously known as MB-SB2) depletes WD rat liver copper dose dependently via fecal excretion down to normal physiological levels within 8 days, superseding the need for continuous treatment. Consequently, we developed a new treatment consisting of repetitive cycles, each of ∼1 week of ARBM101 applications, followed by months of in-between treatment pauses to ensure a healthy long-term survival in WD rats. CONCLUSIONS: ARBM101 safely and efficiently depletes excess liver copper from WD rats, thus allowing for short treatment periods as well as prolonged in-between rest periods.


Assuntos
Degeneração Hepatolenticular , Ratos , Animais , Degeneração Hepatolenticular/tratamento farmacológico , Degeneração Hepatolenticular/metabolismo , Cobre , Eliminação Hepatobiliar , Fígado/metabolismo , Quelantes/farmacologia , Quelantes/uso terapêutico
5.
Hepatology ; 77(4): 1319-1334, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36029129

RESUMO

BACKGROUND AND AIMS: Receptor-interacting protein kinase 3 (RIPK3) mediates NAFLD progression, but its metabolic function is unclear. Here, we aimed to investigate the role of RIPK3 in modulating mitochondria function, coupled with lipid droplet (LD) architecture in NAFLD. APPROACH AND RESULTS: Functional studies evaluating mitochondria and LD biology were performed in wild-type (WT) and Ripk3-/- mice fed a choline-deficient, amino acid-defined (CDAA) diet for 32 and 66 weeks and in CRISPR-Cas9 Ripk3 -null fat-loaded immortalized hepatocytes. The association between hepatic perilipin (PLIN) 1 and 5, RIPK3, and disease severity was also addressed in a cohort of patients with NAFLD and in PLIN1 -associated familial partial lipodystrophy. Ripk3 deficiency rescued impairment in mitochondrial biogenesis, bioenergetics, and function in CDAA diet-fed mice and fat-loaded hepatocytes. Ripk3 deficiency was accompanied by a strong upregulation of antioxidant systems, leading to diminished oxidative stress upon fat loading both in vivo and in vitro. Strikingly, Ripk3-/- hepatocytes displayed smaller size LD in higher numbers than WT cells after incubation with free fatty acids. Ripk3 deficiency upregulated adipocyte and hepatic levels of LD-associated proteins PLIN1 and PLIN5. PLIN1 upregulation controlled LD structure and diminished mitochondrial stress upon free fatty acid overload in Ripk3-/- hepatocytes and was associated with diminished human NAFLD severity. Conversely, a pathogenic PLIN1 frameshift variant was associated with NAFLD and fibrosis, as well as with increased hepatic RIPK3 levels in familial partial lipodystrophy. CONCLUSIONS: Ripk3 deficiency restores mitochondria bioenergetics and impacts LD dynamics. RIPK3 inhibition is promising in ameliorating NAFLD.


Assuntos
Lipodistrofia Parcial Familiar , Hepatopatia Gordurosa não Alcoólica , Humanos , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/patologia , Gotículas Lipídicas , Lipodistrofia Parcial Familiar/metabolismo , Lipodistrofia Parcial Familiar/patologia , Fígado/patologia , Hepatócitos/metabolismo , Metabolismo Energético , Mitocôndrias/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo
6.
Opt Express ; 31(12): 20559-20571, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37381448

RESUMO

Neural networks are a prominent tool for identifying and modeling complex patterns, which are otherwise hard to detect and analyze. While machine learning and neural networks have been finding applications across many areas of science and technology, their use in decoding ultrafast dynamics of quantum systems driven by strong laser fields has been limited so far. Here we use standard deep neural networks to analyze simulated noisy spectra of highly nonlinear optical response of a 2-dimensional gapped graphene crystal to intense few-cycle laser pulses. We show that a computationally simple 1-dimensional system provides a useful "nursery school" for our neural network, allowing it to be retrained to treat more complex 2D systems, recovering the parametrized band structure and spectral phases of the incident few-cycle pulse with high accuracy, in spite of significant amplitude noise and phase jitter. Our results offer a route for attosecond high harmonic spectroscopy of quantum dynamics in solids with a simultaneous, all-optical, solid-state based complete characterization of few-cycle pulses, including their nonlinear spectral phase and the carrier envelope phase.

7.
Liver Int ; 43(10): 2256-2274, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37534739

RESUMO

BACKGROUND AND AIMS: The mechanisms governing the progression of non-alcoholic fatty liver disease (NAFLD) towards steatohepatitis (NASH) and hepatocellular carcinoma (HCC) remain elusive. Here, we evaluated the role of hsa-miRNA-21-5p in NASH-related hepatocarcinogenesis. METHODS: Hepatic hsa-miR-21-5p expression was evaluated in two cohorts of patients with biopsy-proven NAFLD (n = 199) or HCC (n = 366 HCC and n = 11 NAFLD-HCC). Serum/liver metabolomic profiles were correlated with hsa-miR-21-5p in NAFLD obese patients. Wild-type (WT) and Mir21 KO mice were fed a choline-deficient, amino acid-defined (CDAA) diet for 32 and 66 weeks to induce NASH and NASH-HCC, respectively. RESULTS: In obese individuals, hsa-miR-21-5p expression increased with NAFLD severity and associated with a hepatic lipotoxic profile. CDAA-fed WT mice displayed increased hepatic mmu-miR-21-5p levels and progressively developed NASH and fibrosis, with livers presenting macroscopically discernible pre-neoplastic nodules, hyperplastic foci and deregulated cancer-related pathways. Mir21 KO mice exhibited peroxisome-proliferator-activated receptor α (PPARα) activation, augmented mitochondrial activity, reduced liver injury and NAS below the threshold for NASH diagnosis, with the pro-inflammatory/fibrogenic milieu reversing to baseline levels. In parallel, Mir21 KO mice displayed reduced number of pre-neoplastic nodules, hepatocyte proliferation and activation of oncogenic signalling, being protected from NASH-associated carcinogenesis. The hsa-miRNA-21-5p/PPARα pathway was similarly deregulated in patients with HCC- or NASH-related HCC, correlating with HCC markers and worse prognosis. CONCLUSIONS: Hsa-miR-21-5p is a key inducer of whole-spectrum NAFLD progression, from simple steatosis to NASH and NASH-associated carcinogenesis. The inhibition of hsa-miR-21-5p, leading to a pro-metabolic profile, might constitute an appealing therapeutic approach to ameliorate NASH and prevent progression towards HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/patologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , PPAR alfa , Fígado/patologia , Carcinogênese/genética , Carcinogênese/metabolismo , Carcinogênese/patologia , Obesidade/metabolismo , Colina/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo
8.
J Hepatol ; 77(1): 177-190, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35217064

RESUMO

BACKGROUND & AIMS: Cholangiocarcinoma (CCA) comprises a heterogeneous group of malignant tumors associated with dismal prognosis. Alterations in post-translational modifications (PTMs), including NEDDylation, result in abnormal protein dynamics, cell disturbances and disease. Herein, we investigate the role of NEDDylation in CCA development and progression. METHODS: Levels and functions of NEDDylation, together with response to pevonedistat (NEDDylation inhibitor) or CRISPR/Cas9 against NAE1 were evaluated in vitro, in vivo and/or in patients with CCA. The development of preneoplastic lesions in Nae1+/- mice was investigated using an oncogene-driven CCA model. The impact of NEDDylation in CCA cells on tumor-stroma crosstalk was assessed using CCA-derived cancer-associated fibroblasts (CAFs). Proteomic analyses were carried out by mass-spectrometry. RESULTS: The NEDDylation machinery was found overexpressed and overactivated in human CCA cells and tumors. Most NEDDylated proteins found upregulated in CCA cells, after NEDD8-immunoprecipitation and further proteomics, participate in the cell cycle, proliferation or survival. Genetic (CRISPR/Cas9-NAE1) and pharmacological (pevonedistat) inhibition of NEDDylation reduced CCA cell proliferation and impeded colony formation in vitro. NEDDylation depletion (pevonedistat or Nae1+/- mice) halted tumorigenesis in subcutaneous, orthotopic, and oncogene-driven models of CCA in vivo. Moreover, pevonedistat potentiated chemotherapy-induced cell death in CCA cells in vitro. Mechanistically, impaired NEDDylation triggered the accumulation of both cullin RING ligase and NEDD8 substrates, inducing DNA damage and cell cycle arrest. Furthermore, impaired NEDDylation in CCA cells reduced the secretion of proteins involved in fibroblast activation, angiogenesis, and oncogenic pathways, ultimately hampering CAF proliferation and migration. CONCLUSION: Aberrant protein NEDDylation contributes to cholangiocarcinogenesis by promoting cell survival and proliferation. Moreover, NEDDylation impacts the CCA-stroma crosstalk. Inhibition of NEDDylation with pevonedistat may represent a potential therapeutic strategy for patients with CCA. LAY SUMMARY: Little is known about the role of post-translational modifications of proteins in cholangiocarcinoma development and progression. Herein, we show that protein NEDDylation is upregulated and hyperactivated in cholangiocarcinoma, promoting tumor growth. Pharmacological inhibition of NEDDylation halts cholangiocarcinogenesis and could be an effective therapeutic strategy to tackle these tumors.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Animais , Neoplasias dos Ductos Biliares/etiologia , Ductos Biliares Intra-Hepáticos , Linhagem Celular Tumoral , Colangiocarcinoma/etiologia , Humanos , Camundongos , Modelos Teóricos , Proteômica , Transdução de Sinais
9.
Opt Express ; 30(17): 30347-30355, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36242140

RESUMO

2D materials with broken inversion symmetry posses an extra degree of freedom, the valley pseudospin, that labels in which of the two energy-degenerate crystal momenta, K or K', the conducting carriers are located. It has been shown that shining circularly-polarized light allows to achieve close to 100% of valley polarization, opening the way to valley-based transistors. Yet, switching of the valley polarization is still a key challenge for the practical implementation of such devices due to the short valley lifetimes. Recent progress in ultrashort laser technology now allows to produce trains of attosecond pulses with controlled phase and polarization between the pulses. Taking advantage of such technology, we introduce a coherent control protocol to turn on, off and switch the valley polarization at faster timescales than electron-hole decoherence and valley depolarization, that is, an ultrafast optical valley switch. We theoretically demonstrate the protocol for hBN and MoS2 monolayers calculated from first principles. Additionally, using two time-delayed linearly-polarized pulses with perpendicular polarization, we show that we can extract the electronic dephasing time T2 from the valley Hall conductivity.

10.
Acta Pharmacol Sin ; 43(11): 2895-2904, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35468992

RESUMO

Angiotensin-converting enzyme 2 (ACE2) is the receptor of COVID-19 pathogen SARS-CoV-2, but the transcription factors (TFs) that regulate the expression of the gene encoding ACE2 (ACE2) have not been systematically dissected. In this study we evaluated TFs that control ACE2 expression, and screened for small molecule compounds that could modulate ACE2 expression to block SARS-CoV-2 from entry into lung epithelial cells. By searching the online datasets we found that 24 TFs might be ACE2 regulators with signal transducer and activator of transcription 3 (Stat3) as the most significant one. In human normal lung tissues, the expression of ACE2 was positively correlated with phosphorylated Stat3 (p-Stat3). We demonstrated that Stat3 bound ACE2 promoter, and controlled its expression in 16HBE cells stimulated with interleukin 6 (IL-6). To screen for medicinal compounds that could modulate ACE2 expression, we conducted luciferase assay using HLF cells transfected with ACE2 promoter-luciferase constructs. Among the 64 compounds tested, 6-O-angeloylplenolin (6-OAP), a sesquiterpene lactone in Chinese medicinal herb Centipeda minima (CM), represented the most potent ACE2 repressor. 6-OAP (2.5 µM) inhibited the interaction between Stat3 protein and ACE2 promoter, thus suppressed ACE2 transcription. 6-OAP (1.25-5 µM) and its parental medicinal herb CM (0.125%-0.5%) dose-dependently downregulated ACE2 in 16HBE and Beas-2B cells; similar results were observed in the lung tissues of mice following administration of 6-OAP or CM for one month. In addition, 6-OAP/CM dose-dependently reduced IL-6 production and downregulated chemokines including CXCL13 and CX3CL1 in 16HBE cells. Moreover, we found that 6-OAP/CM inhibited the entry of SARS-CoV-2 S protein pseudovirus into target cells. These results suggest that 6-OAP/CM are ACE2 inhibitors that may potentially protect lung epithelial cells from SARS-CoV-2 infection.


Assuntos
Enzima de Conversão de Angiotensina 2 , Tratamento Farmacológico da COVID-19 , Camundongos , Humanos , Animais , SARS-CoV-2 , Interleucina-6/metabolismo , Pulmão/metabolismo , Células Epiteliais
11.
Gut ; 70(12): 2359-2372, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33361348

RESUMO

OBJECTIVE: Receptor-interacting protein kinase 3 (RIPK3) is a key player in necroptosis execution and an emerging metabolic regulator, whose contribution to non-alcoholic fatty liver disease (NAFLD) is controversial. We aimed to clarify the impact of RIPK3 signalling in the pathogenesis of human and experimental NAFLD. DESIGN: RIPK3 levels were evaluated in two large independent cohorts of patients with biopsy proven NAFLD diagnosis and correlated with clinical and biochemical parameters. Wild-type (WT) or Ripk3-deficient (Ripk3-/-) mice were fed a choline-deficient L-amino acid-defined diet (CDAA) or an isocaloric control diet for 32 and 66 weeks. RESULTS: RIPK3 increased in patients with non-alcoholic steatohepatitis (NASH) in both cohorts, correlating with hepatic inflammation and fibrosis. Accordingly, Ripk3 deficiency ameliorated CDAA-induced inflammation and fibrosis in mice at both 32 and 66 weeks. WT mice on the CDAA diet for 66 weeks developed preneoplastic nodules and displayed increased hepatocellular proliferation, which were reduced in Ripk3-/- mice. Furthermore, Ripk3 deficiency hampered tumourigenesis. Intriguingly, Ripk3-/- mice displayed increased body weight gain, while lipidomics showed that deletion of Ripk3 shifted hepatic lipid profiles. Peroxisome proliferator-activated receptor γ (PPARγ) was increased in Ripk3-/- mice and negatively correlated with hepatic RIPK3 in patients with NAFLD. Mechanistic studies established a functional link between RIPK3 and PPARγ in controlling fat deposition and fibrosis. CONCLUSION: Hepatic RIPK3 correlates with NAFLD severity in humans and mice, playing a key role in managing liver metabolism, damage, inflammation, fibrosis and carcinogenesis. Targeting RIPK3 and its intricate signalling arises as a novel promising approach to treat NASH and arrest disease progression.


Assuntos
Metabolismo dos Lipídeos/genética , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Animais , Biomarcadores/metabolismo , Carcinogênese/genética , Carcinogênese/metabolismo , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Progressão da Doença , Humanos , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Camundongos , Estudos Prospectivos
12.
BMC Genomics ; 22(1): 243, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33827435

RESUMO

BACKGROUND: Altica (Coleoptera: Chrysomelidae) is a highly diverse and taxonomically challenging flea beetle genus that has been used to address questions related to host plant specialization, reproductive isolation, and ecological speciation. To further evolutionary studies in this interesting group, here we present a draft genome of a representative specialist, Altica viridicyanea, the first Alticinae genome reported thus far. RESULTS: The genome is 864.8 Mb and consists of 4490 scaffolds with a N50 size of 557 kb, which covered 98.6% complete and 0.4% partial insect Benchmarking Universal Single-Copy Orthologs. Repetitive sequences accounted for 62.9% of the assembly, and a total of 17,730 protein-coding gene models and 2462 non-coding RNA models were predicted. To provide insight into host plant specialization of this monophagous species, we examined the key gene families involved in chemosensation, detoxification of plant secondary chemistry, and plant cell wall-degradation. CONCLUSIONS: The genome assembled in this work provides an important resource for further studies on host plant adaptation and functionally affiliated genes. Moreover, this work also opens the way for comparative genomics studies among closely related Altica species, which may provide insight into the molecular evolutionary processes that occur during ecological speciation.


Assuntos
Besouros , Sifonápteros , Animais , Besouros/genética , Evolução Molecular , Genoma , Genômica
13.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(5): 489-494, 2020 May 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-32879095

RESUMO

To propose the architectural layout for the big general hospital in the face of public health emergencies, we analyzed the conditions, methods, problems and countermeasures for the reconstruction of the isolation ward from the existing medical building layout of a general hospital. The affected areas met the requirements of isolation ward in the reconstruction, and realized the corresponding partition and separation of people. But the cost of occupying the medical room should be concerned. General hospital should be alerted to potential risks of public health emergencies. The characteristics of different construction types, defects, and the function of the hospital should be considered in the construction, rebuilding, and expansion of the hospital, which shouldnot only meet the needs of the development of the hospital daily usage but also consider dealing with emergent public health events. We can adopt the reasonable layout, including setting up a firewall-like device between the channel and the floor, an ordinary ward at ordinary times, and an independent space for emergency by pulling down the gate. This strategy can not only avoid the problem of low utilization rate of the space occupied by the corresponding area in the ward for diseases spread by air and droplets, maximizing the efficiency of the medical site, but also avoid the problem of emergency response to the temporary reconstruction.


Assuntos
Emergências , Arquitetura de Instituições de Saúde , Hospitais Gerais , Saúde Pública , Serviço Hospitalar de Emergência , Humanos
14.
Clin Sci (Lond) ; 133(22): 2245-2264, 2019 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-31742325

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is a significant public health concern, owing to its high prevalence, progressive nature and lack of effective medical therapies. NAFLD is a complex and multifactorial disease involving the progressive and concerted action of factors that contribute to the development of liver inflammation and eventually fibrosis. Here, we summarize fundamental molecular mechanisms underlying the pathogenesis of non-alcoholic steatohepatitis (NASH), how they are interrelated and possible translation to clinical applications. We focus on processes triggering and exacerbating apoptotic signalling in the liver of NAFLD patients and their metabolic and pathological implications. Indeed, liver injury and inflammation are cardinal histopathological features of NASH, a duo in which derailment of apoptosis is of paramount importance. In turn, the liver houses a very high number of mitochondria, crucial metabolic unifiers of both extrinsic and intrinsic signals that converge in apoptosis activation. The role of lifestyle options is also dissected, highlighting the management of modifiable risk factors, such as obesity and harmful alcohol consumption, influencing apoptosis signalling in the liver and ultimately NAFLD progression. Integrating NAFLD-associated pathologic mechanisms in the cell death context could provide clues for a more profound understating of the disease and pave the way for novel rational therapies.


Assuntos
Apoptose , Hepatopatia Gordurosa não Alcoólica/etiologia , Animais , Humanos , Inflamação/metabolismo , Estilo de Vida , Metabolismo dos Lipídeos , MicroRNAs/metabolismo , Dinâmica Mitocondrial , Necroptose , Hepatopatia Gordurosa não Alcoólica/metabolismo , Estresse Oxidativo
15.
Liver Int ; 39 Suppl 1: 108-122, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30843325

RESUMO

The high mortality rate of cholangiocarcinoma (CCA) is due, in part, to the lack of non-invasive approaches able to accurately detect this silent tumour at early stages, when therapeutic options can be potentially curative or may at least increase the overall survival of patients. The fact that the majority of CCA tumours are not linked to any known aetiological factor highly compromises the monitoring of patients at risk for tumour development and also their early diagnosis. Combination of clinical/biochemical features, imaging techniques and analysis of non-specific tumour biomarkers in serum are commonly used to help in the diagnosis of CCA, but tumour biopsy is usually required to confirm the diagnosis. Moreover, no prognostic biomarkers are currently used in the clinical setting, deserving more innovative research, and international validation and consensus. Important efforts have been made in the last few years to identify accurate non-invasive biomarkers, by using innovative techniques and high-throughput omics technologies. This review summarizes and discusses the advances in the investigation of novel diagnostic and prognostic biomarkers in CCA and envisions the future directions in this field of research.


Assuntos
Neoplasias dos Ductos Biliares/diagnóstico , Biomarcadores Tumorais/análise , Colangiocarcinoma/diagnóstico , Neoplasias dos Ductos Biliares/mortalidade , Neoplasias dos Ductos Biliares/patologia , Biópsia , Colangiocarcinoma/mortalidade , Colangiocarcinoma/patologia , Diagnóstico Precoce , Humanos , Prognóstico , Proteômica
17.
Liver Int ; 38(3): 523-531, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28853202

RESUMO

BACKGROUND & AIMS: Ursodeoxycholic acid (UDCA) is a secondary hydrophilic bile acid (BA) used as therapy for a range of hepatobiliary diseases. Its efficacy in non-alcoholic fatty liver disease (NAFLD) is still under debate. Here, we aimed to decipher molecular mechanisms of UDCA in regulating endoplasmic reticulum (ER) homeostasis, apoptosis and oxidative stress in morbidly obese patients. METHODS: In this randomized controlled pharmacodynamic study, liver and serum samples from 40 well-matched morbidly obese NAFLD-patients were analysed. Patients received UDCA (20 mg/kg/d) or no treatment 3 weeks before samples were obtained during bariatric surgery. RESULTS: Patients treated with UDCA displayed higher scoring of steatosis (S), activity (A) and fibrosis (F), the so called SAF-scoring. UDCA partially disrupted ER homeostasis by inducing the expression of the ER stress markers CHOP and GRP78. However, ERDJ4 and sXBP1 levels were unaffected. Enhanced CHOP expression, a suggested pro-apoptotic trigger, failed to induce apoptosis via BAK and BAX in the UDCA treated group. Potentially pro-apoptotic miR-34a was reduced in the vesicle-free fraction in serum but not in liver after UDCA treatment. Thiobarbituric acid reactive substances, 4-hydroxynonenal and mRNA levels of several oxidative stress indicators remained unchanged after UDCA treatment. CONCLUSION: Our data suggest that UDCA treatment has ambivalent effects in NAFLD patients. While increased SAF-scores and elevated CHOP levels may be disadvantageous in the UDCA treated cohort, UDCA's cytoprotective properties potentially changed the apoptotic threshold as reflected by absent induction of pro-apoptotic triggers. UDCA treatment failed to improve the oxidative stress status in NAFLD patients.


Assuntos
Apoptose/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Obesidade Mórbida/complicações , Estresse Oxidativo/efeitos dos fármacos , Ácido Ursodesoxicólico/uso terapêutico , Retículo Endoplasmático/metabolismo , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Humanos , Fígado/metabolismo , MicroRNAs/sangue , Hepatopatia Gordurosa não Alcoólica/metabolismo , Suécia , Fator de Transcrição CHOP/genética , Fator de Transcrição CHOP/metabolismo , Resposta a Proteínas não Dobradas/efeitos dos fármacos
18.
Cladistics ; 34(2): 113-130, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34645082

RESUMO

With efficient sequencing techniques, full mitochondrial genomes are rapidly replacing other widely used markers, such as the nuclear rRNA genes, for phylogenetic analysis but their power to resolve deep levels of the tree remains controversial. We studied phylogenetic relationships of leaf beetles (Chrysomelidae) in the tribes Galerucini and Alticini (root worms and flea beetles) based on full mitochondrial genomes (103 newly sequenced), and compared their performance to the widely sequenced nuclear rRNA genes (full 18S, partial 28S). Our results show that: (i) the mitogenome is phylogenetically informative from subtribe to family level, and the per-nucleotide contribution to nodal support is higher than that of rRNA genes, (ii) the Galerucini and Alticini are reciprocally monophyletic sister groups, if the classification is adjusted to accommodate several 'problematic genera' that do not fit the dichotomy of lineages based on the presence (Alticini) or absence (Galerucini) of the jumping apparatus, and (iii) the phylogenetic results suggest a new classification system of Galerucini with eight subtribes: Oidina, Galerucina, Hylaspina, Metacyclina, Luperina, Aulacophorina, Diabroticina and Monoleptina.

19.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 38(1): 93-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26956864

RESUMO

OBJECTIVE: To investigate the computed tomographic (CT) and pathological features of primary pulmonary sarcomatoid carcinoma (PSC). METHODS: The clinical data and CT images of 20 patients with pathologically confirmed PSC were retrospectively analyzed. RESULTS: Solitary pulmonary mass was identified in 18 patients and multiple pulmonary masses in 2 patients, amounting to 22 masses. There were 17 peripheral masses and 5 central masses, including 11 masses larger than 5 cm. The smooth margin was identified in 9 masses, deep lobulation and/or spinous protuberance in 11 masses, and ill-defined margin in 2 masses. Pleural indentation was identified in 2 masses and pleural thickening with wide basement was identified in 14 masses. On plain CT, cavity was observed in 5 masses, hypo-density in 7 masses, and homogeneous density in 10 masses. On contrast-enhanced CT scanning, irregular ring/patchy enhancement were shown in 15 masses and slightly homogenous enhancement in 2 masses. Of all patients, 6 patients had unilateral or bilateral hilar and/or mediastinal lymphadenopathy. There were 16 pleomorphic carcinomas and 4 spindle cell carcinomas. Immunohistochemically, anti-pan cytokeratin antibody was positive in 13 patients, cytokeratin was positive in 8 patients, Vimentin was positive in 15 patients, epithelial membrane antigen was positive in 1 patient, and thyroid transcription factor-1 was positive in 8 patients. CONCLUSION: PSC has some specific CT features; however, the final confirmation of PSC still depends on pathological and immunohistochemical examinations.


Assuntos
Neoplasias Pulmonares/patologia , Sarcoma , Humanos , Proteínas Nucleares , Estudos Retrospectivos , Fator Nuclear 1 de Tireoide , Tomografia Computadorizada por Raios X , Fatores de Transcrição
20.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 41(12): 1328-1333, 2016 Dec 28.
Artigo em Chinês | MEDLINE | ID: mdl-28070047

RESUMO

OBJECTIVE: To analyze the clinical characteristics of continuous ambulatory peritoneal dialysis (CAPD) associated peritonitis in the tertiary hospitals and to discuss the preventive and therapeutic strategy.
 Methods: The clinical characteristics, pathogens, resistance and outcomes of 126 CAPD associated peritonitis in 104 patients from Jan, 2013 to June, 2016, were retrospectively analyzed.
 Results: Among the patients, the incidence rates of abdominal pain, fever, diarrhea and emesis were 104 (82.54%), 56 (44.44%), 49 (38.89%), and 31 (23.60%), respectively. Among them, 88 patients suffered peritonitis once, other 16 patients suffered multiple peritonitis or recurrent peritonitis for 38 times. Among the 38 times, the numbers for recurrent, repeated or catheter-associated peritonitis were 2, 2, or 3, respectively. Peritoneal fluids from 103 cases were cultured, and 64 cases were positive in bacteria, with a rate of 62.14%. A total of 70 strains of bacteria were separated, including 42 strains of gram-positive bacteria, 21 strains of gram-negative bacteria, and 7 strains of fungus. The most common gram-positive pathogens were Staphylococcus epidermidis, Enterococcus faecalis and Staphylococcus haemolyticus, while Escherichia coli, Klebsiella pneumoniae and Klebsiella pneumoniae were the most common gram-negative bacteria. Candida albicans was the major fungal pathogens. Gram-positive cocci showed resistance to gentamycin, levofloxacin, moxifloxacin, vancomycin and linezolid, with a rate at 20.00%, 36.11%, 5%, 0%, and 0%, respectively. The gram-negative bacilli were resistent to cefoperazone/sulbactam, gentamycin, cephazolin, and ceftazidime, with a rate at 6.25%, 10.53%, 64.29%, and 15.38%, respectively. There were no imipenem, amikacin, piperacillin/tazobactam-resistant strains were found.
 Conclusion: The most common pathogen causing CAPD associated peritonitis is gram-positive bacteria. It is crucial to take the anti-infection therapy for CAPD associated peritonitis early. The positive rates for bacterial culture need to be enhanced through improvement of methods. At the same time, doctors could improve the outcome of CAPD associated peritonitis by adjusting the medication according to the drug sensitivity results.


Assuntos
Infecções Bacterianas/epidemiologia , Diálise Peritoneal Ambulatorial Contínua/efeitos adversos , Peritonite/epidemiologia , Peritonite/microbiologia , Dor Abdominal/epidemiologia , Antibacterianos , Bactérias , Infecções Bacterianas/microbiologia , Candidíase/epidemiologia , Catéteres/efeitos adversos , Catéteres/microbiologia , Diarreia/epidemiologia , Farmacorresistência Bacteriana , Enterococcus faecalis , Escherichia coli , Febre/epidemiologia , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Humanos , Imipenem , Klebsiella pneumoniae , Testes de Sensibilidade Microbiana , Micoses/epidemiologia , Ácido Penicilânico/análogos & derivados , Diálise Peritoneal , Peritonite/complicações , Piperacilina , Combinação Piperacilina e Tazobactam , Recidiva , Estudos Retrospectivos , Staphylococcus epidermidis , Staphylococcus haemolyticus , Vômito/epidemiologia
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