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1.
Brief Bioinform ; 24(4)2023 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-37328692

RESUMO

Protein complexes are key functional units in cellular processes. High-throughput techniques, such as co-fractionation coupled with mass spectrometry (CF-MS), have advanced protein complex studies by enabling global interactome inference. However, dealing with complex fractionation characteristics to define true interactions is not a simple task, since CF-MS is prone to false positives due to the co-elution of non-interacting proteins by chance. Several computational methods have been designed to analyze CF-MS data and construct probabilistic protein-protein interaction (PPI) networks. Current methods usually first infer PPIs based on handcrafted CF-MS features, and then use clustering algorithms to form potential protein complexes. While powerful, these methods suffer from the potential bias of handcrafted features and severely imbalanced data distribution. However, the handcrafted features based on domain knowledge might introduce bias, and current methods also tend to overfit due to the severely imbalanced PPI data. To address these issues, we present a balanced end-to-end learning architecture, Software for Prediction of Interactome with Feature-extraction Free Elution Data (SPIFFED), to integrate feature representation from raw CF-MS data and interactome prediction by convolutional neural network. SPIFFED outperforms the state-of-the-art methods in predicting PPIs under the conventional imbalanced training. When trained with balanced data, SPIFFED had greatly improved sensitivity for true PPIs. Moreover, the ensemble SPIFFED model provides different voting schemes to integrate predicted PPIs from multiple CF-MS data. Using the clustering software (i.e. ClusterONE), SPIFFED allows users to infer high-confidence protein complexes depending on the CF-MS experimental designs. The source code of SPIFFED is freely available at: https://github.com/bio-it-station/SPIFFED.


Assuntos
Mapeamento de Interação de Proteínas , Proteínas , Mapeamento de Interação de Proteínas/métodos , Proteínas/química , Algoritmos , Mapas de Interação de Proteínas , Software
2.
J Pathol ; 259(4): 428-440, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36641765

RESUMO

Anti-programmed cell death 1 (anti-PD-1) therapy shows definite but modest activity in patients with advanced/metastatic head and neck squamous cell carcinoma (HNSCC). Preliminary evidence suggests that SN-38, an activated form of irinotecan that increases expression of the transcription factor FoxO3a, can suppress programmed cell death ligand-1 (PD-L1) expression in breast and ovarian tumor models. We analyzed the SN-38-mediated activation of natural killer cells in vitro and explored the efficacy of SN-38 in combination with anti-PD-1 for treatment in vivo. In vitro, SN-38 enhanced the expression of FoxO3a and reduced the expression of c-Myc and PD-L1 dose-dependently in tumor cells. Low-dose SN-38 increased interferon-γ secretion by NK cells and promoted NK cell-mediated cytotoxicity in tumor cells. In vivo studies revealed that at non-cytotoxic drug concentrations, SN-38 significantly enhanced anti-PD-1 activity in suppressing murine tumor growth. We found increased NK cell and CD8+ T-cell infiltration in post-treatment tumors. RNA-seq analysis indicated that SN-38 increased the enrichment of immune cells and biological function genes related to the immune responses. SN-38 is a potentially beneficial adjunct to checkpoint inhibitor therapy in HNSCC. Further studies exploring its mechanism of action and possible applications are necessary. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Assuntos
Antígeno B7-H1 , Neoplasias de Cabeça e Pescoço , Animais , Humanos , Camundongos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/genética , Irinotecano/farmacologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Resultado do Tratamento
3.
J Formos Med Assoc ; 2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38185618

RESUMO

OBJECTIVES: Studies have demonstrated that high-speed jaw-opening exercises are effective in improving swallowing function. However, there has been no objective tool available for monitoring jaw-opening pace. This study aimed to develop an objective tool for monitoring and validating jaw-opening pace and compare it between young and old ages from different age groups. MATERIALS AND METHODS: A load cell plug-in jaw pad connected to an automatic recording and analysis system was used to record jaw-opening motions for offline analysis. We recruited 58 healthy volunteers from different age groups (20-39 y/o; 40-59y/o; 60-79y/o). During a 2-min recording session, each participant was instructed to fully open and close their jaw as quickly as possible while wearing a sensor. Bland-Altman plot, paired t-test and Pearson's correlation test were used to compare the number of jaw-opening motions between manual counting and automatic software analysis. The number of jaw-opening motions during the 2-min recording was compared between the three age groups. RESULTS: Automated analysis of jaw-opening pace was efficient and equally comparable with the traditional manual counting method across the three age groups. A declining trend in jaw-opening pace among the old age group was found but with no statistically significant difference. CONCLUSIONS: A jaw-opening motion monitoring tool with reliable automatic pace analysis software was validated in young and old ages. The jaw-opening pace demonstrated a tendency to decline with age. CLINICAL RELEVANCE: This monitoring tool can also be used to provide visual feedback during jaw-opening motion training in pace control.

4.
J Pediatr ; 260: 113514, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37244580

RESUMO

To examine delay from developmental screening to autism diagnosis, we used real-world health care data from a national research network to estimate the time between these events. We found an average delay of longer than 2 years from first screening to diagnosis, with no significant differences observed by sex, race, or ethnicity.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Humanos , Transtorno do Espectro Autista/diagnóstico , Etnicidade , Prevalência
5.
Int J Mol Sci ; 24(4)2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36835312

RESUMO

Peroxisome proliferator-activated receptor γ (PPARγ) gene mutations in humans and mice lead to whole-body insulin resistance and partial lipodystrophy. It is unclear whether preserved fat depots in partial lipodystrophy are beneficial for whole-body metabolic homeostasis. We analyzed the insulin response and expression of metabolic genes in the preserved fat depots of PpargC/- mice, a familial partial lipodystrophy type 3 (FPLD3) mouse model resulting from a 75% decrease in Pparg transcripts. Perigonadal fat of PpargC/- mice in the basal state showed dramatic decreases in adipose tissue mass and insulin sensitivity, whereas inguinal fat showed compensatory increases. Preservation of inguinal fat metabolic ability and flexibility was reflected by the normal expression of metabolic genes in the basal or fasting/refeeding states. The high nutrient load further increased insulin sensitivity in inguinal fat, but the expression of metabolic genes became dysregulated. Inguinal fat removal resulted in further impairment of whole-body insulin sensitivity in PpargC/- mice. Conversely, the compensatory increase in insulin sensitivity of the inguinal fat in PpargC/- mice diminished as activation of PPARγ by its agonists restored insulin sensitivity and metabolic ability of perigonadal fat. Together, we demonstrated that inguinal fat of PpargC/- mice plays a compensatory role in combating perigonadal fat abnormalities.


Assuntos
Resistência à Insulina , Lipodistrofia Parcial Familiar , PPAR gama , Animais , Humanos , Camundongos , Insulina/metabolismo , Insulina/farmacologia , Resistência à Insulina/genética , Lipodistrofia Parcial Familiar/genética , Mutação , PPAR gama/genética , PPAR gama/metabolismo
6.
Behav Res Methods ; 55(7): 3805-3819, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-36253597

RESUMO

Virtual reality (VR) has been shown to be a potential research tool, yet the gap between traditional and VR behavioral experiment systems poses a challenge for many behavioral researchers. To address the challenge posed, the present study first adopted a modularity design strategy and proposed a five-module architectural framework for a VR behavioral experiment system that aimed to reduce complexity and costs of development. Applying the five-module architectural framework, the present study developed the SkyrimVR-based behavioral experimental framework (SkyBXF) module, a basic experimental framework module that adopted and integrated the classic human behavior experiment structure (i.e., session-block-trial model) with the modifiable VR massive gaming franchise The Elder Scrolls V: Skyrim VR. A modified version of previous behavioral research to investigate the effects of masked peripheral vision on visually-induced motion sickness in an immersive virtual environment was conducted as a proof of concept to showcase the feasibility of the proposed five-module architectural framework and the SkyBXF module developed. Behavioral data acquired through the case study were consistent with those from previous behavioral research. This indicates the viability of the proposed five-module architectural framework and the SkyBXF module developed, and provides proof that future behavioral researchers with minimal programming proficiency, 3D environment development expertise, time, personnel, and resources may reuse ready-to-go resources and behavioral experiment templates offered by SkyBXF to swiftly establish realistic virtual worlds that can be further customized for experimental need on the go.


Assuntos
Pesquisa Comportamental , Realidade Virtual , Humanos , Interface Usuário-Computador
7.
Opt Express ; 30(26): 46944-46955, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36558633

RESUMO

Stimulated Raman scattering is ubiquitous in many high-intensity laser environments. Parametric four-wave mixing between the pump and Raman sidebands can affect the Raman gain, but stringent phase matching requirements and strongly nonlinear dynamics obscure clear understanding of its effects at high laser powers. Here we investigate four-wave mixing in the presence of strong self-focusing and weak ionization at laser powers above the Kerr critical power. Theoretical analysis shows that the plasma generated at focus naturally leads to phase matching conditions suitable for enhanced Raman gain, almost without regard to the initial phase mismatch. Multidimensional nonlinear optical simulations with multiphoton and collisional ionization confirm the enhancement and suggest that it may lead to significantly higher Raman losses in some high-intensity laser environments.

8.
Parasitology ; 148(2): 187-197, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33004090

RESUMO

Steroids have been shown to be beneficial in patients and mice with eosinophilic meningitis caused by Angiostrongylus cantonensis infection; however, the mechanism for this beneficial effect is unknown. We speculated that the effect of steroids in eosinophilic meningitis caused by A. cantonensis infection may be mediated by the downregulation of matrix metallopeptidase-9 (MMP-9) and oxidative stress pathways via glucocorticoid receptors (GRs). We found blood-brain barrier (BBB) dysfunction in mice with eosinophilic meningitis 2-3 weeks after infection as evidenced by increased extravasation of Evans blue and cerebrospinal fluid (CSF) albumin levels. The administration of dexamethasone significantly decreased the amount of Evans blue and CSF albumin. The effect of dexamethasone was mediated by GRs and heat shock protein 70, resulting in subsequent decreases in the expressions of nuclear factor kappa B (NF-κB), c-Jun N-terminal kinase (JNK), and extracellular signal-regulated kinase (ERK) in the CSF and brain parenchymal after 2 weeks of steroid administration. Steroid treatment also decreased CSF/brain homogenate MMP-9 concentrations, but had no effect on CSF MMP-2 levels, indicating that MMP-9 rather than MMP-2 played a major role in BBB dysfunction in mice with eosinophilic meningitis. The concentration of 8-hydroxy-2'-deoxyguanosine (8-OHdG) gradually increased after 1-3 weeks of infection, and the administration of dexamethasone significantly downregulated the concentration of oxidized derivative 8-OHdG in CSF. In conclusion, increased 8-OHdG and MMP-9 concentrations were found in mice with eosinophilic meningitis caused by A. cantonensis infection. The effect of dexamethasone was mediated by GRs and significantly decreased not only the levels of 8-OHdG and MMP-9 but also NF-κB, JNK and ERK.


Assuntos
Dexametasona/administração & dosagem , Regulação para Baixo/efeitos dos fármacos , Glucocorticoides/administração & dosagem , Metaloproteinase 9 da Matriz/genética , Estresse Oxidativo/efeitos dos fármacos , Doenças dos Roedores/parasitologia , Infecções por Strongylida/parasitologia , Angiostrongylus cantonensis/fisiologia , Animais , Eosinofilia/metabolismo , Eosinofilia/parasitologia , Regulação da Expressão Gênica/efeitos dos fármacos , Injeções Intraperitoneais , Metaloproteinase 9 da Matriz/metabolismo , Meningite/metabolismo , Meningite/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Doenças dos Roedores/metabolismo , Infecções por Strongylida/metabolismo
9.
Nature ; 528(7583): 534-8, 2015 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-26701054

RESUMO

Data transport across short electrical wires is limited by both bandwidth and power density, which creates a performance bottleneck for semiconductor microchips in modern computer systems--from mobile phones to large-scale data centres. These limitations can be overcome by using optical communications based on chip-scale electronic-photonic systems enabled by silicon-based nanophotonic devices. However, combining electronics and photonics on the same chip has proved challenging, owing to microchip manufacturing conflicts between electronics and photonics. Consequently, current electronic-photonic chips are limited to niche manufacturing processes and include only a few optical devices alongside simple circuits. Here we report an electronic-photonic system on a single chip integrating over 70 million transistors and 850 photonic components that work together to provide logic, memory, and interconnect functions. This system is a realization of a microprocessor that uses on-chip photonic devices to directly communicate with other chips using light. To integrate electronics and photonics at the scale of a microprocessor chip, we adopt a 'zero-change' approach to the integration of photonics. Instead of developing a custom process to enable the fabrication of photonics, which would complicate or eliminate the possibility of integration with state-of-the-art transistors at large scale and at high yield, we design optical devices using a standard microelectronics foundry process that is used for modern microprocessors. This demonstration could represent the beginning of an era of chip-scale electronic-photonic systems with the potential to transform computing system architectures, enabling more powerful computers, from network infrastructure to data centres and supercomputers.

10.
BMC Womens Health ; 21(1): 270, 2021 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-34246259

RESUMO

BACKGROUND: Malignant obstruction and associated hydronephrosis is a common complication of advanced cervical cancer. Percutaneous nephrostomy (PCN) followed by antegrade stenting is often required to relieve obstruction as retrograde access fails in considerable proportion of such patients. Reno-pleural fistula is a rare complication of PCN which creates a patent connection between the renal collecting system and the thoracic cavity, and urine accumulation in the pleural space can cause pleural effusion (i.e., urinothorax). Upward or downward migration is a complication of indwelling ureteric stents. Further migration with extrusion outside of the urinary tract is uncommon. Herein we present an unprecedented case in adult of ureteric stent upward migration through a reno-pleural fistula into the thoracic cavity managed by thoracoscopy. CASE PRESENTATION: A 66-year-old female was diagnosed of advanced stage cervical cancer with suspicious bladder invasion. Given her bilateral hydronephrosis with impaired renal function, she underwent bilateral PCN and subsequent antegrade ureteric stenting. However, she presented with dyspnea, right back pain, and oliguria four days after bilateral PCN catheter removal. Computed tomography reported massive right pleural effusion and an intrathoracic ureteric stent within reno-pleural fistula. Thoracoscopy with thoracostomy was performed to remove the ureteric stent and urine in right pleural space. A week later, urinothorax had resolved and right PCN was performed again. She was discharged after regaining normal renal function with right PCN and a left ureteric stent in place. CONCLUSIONS: A reno-pleural fistula can serve as a route for ureteric stent migration and that continuous drainage of urine can cause urinothorax once the stent reaches the thoracic cavity. Anytime a supracostal approach is used for PCN, even when using small caliber catheters, clinicians should pay special attention given the risk of pleural injury and subsequent complications.


Assuntos
Fístula , Nefrostomia Percutânea , Adulto , Idoso , Drenagem , Feminino , Fístula/etiologia , Fístula/cirurgia , Humanos , Rim/fisiologia , Stents/efeitos adversos
11.
J Neuroeng Rehabil ; 18(1): 91, 2021 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-34059090

RESUMO

BACKGROUND: Virtual reality and arm cycling have been reported as effective treatments for improving upper limb motor recovery in patients with stroke. Intermittent theta burst stimulation (iTBS) can increase ipsilesional cortical excitability, and has been increasingly used in patients with stroke. However, few studies examined the augmented effect of iTBS on neurorehabilitation program. In this study, we investigated the augmented effect of iTBS on virtual reality-based cycling training (VCT) for upper limb function in patients with stroke. METHODS: In this randomized controlled trial, 23 patients with stroke were recruited. Each patient received either 15 sessions of iTBS or sham stimulation in addition to VCT on the same day. Outcome measures were assessed before and after the intervention. Primary outcome measures for the improvement of upper limb motor function and spasticity were Fugl-Meyer Assessment-Upper Extremity (FMA-UE) and Modified Ashworth Scale Upper-Extremity (MAS-UE). Secondary outcome measures for activity and participation were Action Research Arm Test (ARAT), Nine Hole Peg Test (NHPT), Box and Block Test (BBT) and Motor Activity Log (MAL), and Stroke Impact Scale (SIS). Wilcoxon signed-rank tests were performed to evaluate the effectiveness after the intervention and Mann-Whitney U tests were conducted to compare the therapeutic effects between two groups. RESULTS: At post-treatment, both groups showed significant improvement in FMA-UE and ARAT, while only the iTBS + VCT group demonstrated significant improvement in MAS-UE, BBT, NHPT, MAL and SIS. The Mann-Whitney U tests revealed that the iTBS + VCT group has presented greater improvement than the sham group significantly in MAS-UE, MAL-AOU and SIS. However, there were no significant differences in the changes of the FMA-UE, ARAT, BBT, NHPT and MAL-QOM between groups. CONCLUSIONS: Intermittent TBS showed augmented efficacy on VCT for reducing spasticity, increasing actual use of the affected upper limb, and improving participation in daily life in stroke patients. This study provided an integrated innovative intervention, which may be a promising therapy to improve upper limb function recovery in stroke rehabilitation. However, this study has a small sample size, and thus a further larger-scale study is warranted to confirm the treatment efficacy. Trial registration This trial was registered under ClinicalTrials.gov ID No. NCT03350087, retrospectively registered, on November 22, 2017.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Realidade Virtual , Humanos , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/complicações , Estimulação Magnética Transcraniana , Resultado do Tratamento , Extremidade Superior
12.
Int J Mol Sci ; 22(5)2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33808007

RESUMO

Obesity and its associated conditions, such as type 2 diabetes mellitus (T2DM) and nonalcoholic fatty liver disease (NAFLD), are a particular worldwide health problem at present. Momordica cochinchinensis (MC) is consumed widely in Southeast Asia. However, whether it has functional effects on fat-induced metabolic syndrome remains unclear. This study was conducted to examine the prevention effect of Momordica cochinchinensis aril (MCA) on obesity, non-alcoholic fatty liver and insulin resistance in mice. MCA protected the mice against high-fat diet (HFD)-induced body weight gain, hyperlipidemia and hyperglycemia, compared with mice that were not treated. MCA inhibited the expansion of adipose tissue and adipocyte hypertrophy. In addition, the insulin sensitivity-associated index that evaluates insulin function was also significantly restored. MCA also regulated the secretion of adipokines in HFD-induced obese mice. Moreover, hepatic fat accumulation and liver damage were reduced, which suggested that fatty liver was prevented by MCA. Furthermore, MCA supplementation suppressed hepatic lipid accumulation by activation of the AMP-activated protein kinase (AMPK) and peroxisome proliferator-activated receptor-alpha (PPAR-alpha) signaling pathway in the human fatty liver HuS-E/2 cell model. Our data indicate that MCA altered the microbial contents of the gut and modulated microbial dysbiosis in the host, and consequently is involved in the prevention of HFD-induced adiposity, insulin resistance and non-alcoholic fatty liver disease.


Assuntos
Frutas/química , Microbioma Gastrointestinal/efeitos dos fármacos , Momordica/química , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Obesidade/tratamento farmacológico , Extratos Vegetais/farmacologia , Animais , Dieta Hiperlipídica/efeitos adversos , Masculino , Camundongos , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Obesidade/induzido quimicamente , Obesidade/metabolismo , Obesidade/patologia , Extratos Vegetais/química
13.
Molecules ; 26(20)2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34684832

RESUMO

Androgens have been shown to have a beneficial effect on brain injury and lower reactive astrocyte expression after TBI. Androgen receptors (ARs) are known to mediate the neuroprotective effects of androgens. However, whether ARs play a crucial role in TBI remains unknown. In this study, we investigated the role of ARs in TBI pathophysiology, using AR knockout (ARKO) mice. We used the controlled cortical impact model to produce primary and mechanical brain injuries and assessed motor function and brain-lesion volume. In addition, the AR knockout effects on necrosis and autophagy were evaluated after TBI. AR knockout significantly increased TBI-induced expression of the necrosis marker alpha-II-spectrin breakdown product 150 and astrogliosis marker glial fibrillary acidic protein. In addition, the TBI-induced astrogliosis increase in ARKO mice lasted for three weeks after a TBI. The autophagy marker Beclin-1 was also enhanced in ARKO mice compared with wild-type mice after TBI. Our results also indicated that ARKO mice showed a more unsatisfactory performance than wild-type mice in a motor function test following TBI. Further, they were observed to have more severe lesions than wild-type mice after injury. These findings strongly suggest that ARs play a role in TBI.


Assuntos
Lesões Encefálicas Traumáticas/fisiopatologia , Receptores Androgênicos/deficiência , Animais , Autofagia , Proteína Beclina-1/metabolismo , Encéfalo/fisiologia , Encéfalo/fisiopatologia , Lesões Encefálicas Traumáticas/etiologia , Lesões Encefálicas Traumáticas/patologia , Modelos Animais de Doenças , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Humanos , Masculino , Camundongos , Camundongos Knockout , Transtornos Motores/patologia , Transtornos Motores/fisiopatologia , Receptores Androgênicos/genética , Receptores Androgênicos/fisiologia , Espectrina/metabolismo
14.
Molecules ; 26(9)2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33926142

RESUMO

In this novel study, we isolated 28 compounds from the leaves of Aquilaria sinensis (Lour.) Gilg based on a bioassay-guided procedure and also discovered the possible matrix metalloprotease 2 (MMP-2) and 9 (MMP-9) modulatory effect of pheophorbide A (PA). To evaluate the regulatory activity on MMP-2 and MMP-9, the HT-1080 human fibrosarcoma cells were treated with various concentrations of extracted materials and isolated compounds. PA was extracted by methanol from the leaves of A. sinensis and separated from the fraction of the partitioned ethyl acetate layer. PA is believed to be an active component for MMP expression since it exhibited significant stimulation on MMP-2 and proMMP-9 activity. When treating with 50 µM of PA, the expression of MMP-2 and MMP-9 were increased 1.9-fold and 2.3-fold, respectively. PA also exhibited no cytotoxicity against HT-1080 cells when the cell viability was monitored. Furthermore, no significant MMP activity was observed when five PA analogues were evaluated. This study is the first to demonstrate that C-17 of PA is the deciding factor in determining the bioactivity of the compound. The MMP-2 and proMMP-9 modulatory activity of PA indicate its potential applications for reducing scar formation and comparative medical purposes.


Assuntos
Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/genética , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/química , Thymelaeaceae/química , Linhagem Celular Tumoral , Humanos , Estrutura Molecular , Compostos Fitoquímicos/química , Extratos Vegetais/química
15.
J Virol ; 93(22)2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31462559

RESUMO

Hepatitis C virus (HCV) NS3 protein possesses protease and helicase activities and is considered an oncoprotein in virus-derived hepatocellular carcinoma. The NS3-associated oncogenesis has been studied but not fully understood. In this study, we have identified novel interactions of the NS3 protein with DNA repair factors, Werner syndrome protein (WRN) and Ku70, in both an HCV subgenomic replicon system and Huh7 cells expressing NS3. HCV NS3 protein inhibits WRN-mediated DNA repair and reduces the repair efficiency of nonhomologous end joining. It interferes with Ku70 recruitment to the double-strand break sites and alters the nuclear distribution of WRN-Ku repair complex. In addition, WRN is a substrate of the NS3/4A protease; the level of WRN protein is regulated by both the proteasome degradation pathway and HCV NS3/4A protease activity. The dual role of HCV NS3 and NS3/4A proteins in regulating the function and expression level of the WRN protein intensifies the effect of impairment on DNA repair. This may lead to an accumulation of DNA mutations and genome instability and, eventually, tumor development.IMPORTANCE HCV infection is a worldwide problem of public health and a major contributor to hepatocellular carcinoma. The single-stranded RNA virus with RNA-dependent RNA polymerase experiences a high error rate and develops strategies to escape the immune system and hepatocarcinogenesis. Studies have revealed the involvement of HCV proteins in the impairment of DNA repair. The present study aimed to further elucidate mechanisms by which the viral NS3 protein impairs the repair of DNA damage. Our results clearly indicate that HCV NS3/4A protease targets WRN for degradation, and, at the same time, diminishes the repair efficiency of nonhomologous end joining by interfering with the recruitment of Ku protein to the DNA double-strand break sites. The study describes a novel mechanism by which the NS3 protein influences DNA repair and provides new insight into the molecular mechanism of HCV pathogenesis.


Assuntos
Reparo do DNA por Junção de Extremidades , Hepacivirus/genética , Hepacivirus/metabolismo , Proteínas não Estruturais Virais/metabolismo , Helicase da Síndrome de Werner/metabolismo , Linhagem Celular , DNA/metabolismo , Quebras de DNA de Cadeia Dupla , Dano ao DNA , Reparo do DNA/fisiologia , Proteínas de Ligação a DNA/metabolismo , Exodesoxirribonucleases/metabolismo , Células HEK293 , Hepatite C Crônica/genética , Humanos , Autoantígeno Ku/genética , RNA Polimerase Dependente de RNA/genética , Proteínas não Estruturais Virais/genética , Helicase da Síndrome de Werner/fisiologia
16.
Opt Lett ; 45(15): 4344-4347, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32735294

RESUMO

Meter-scale nonlinear propagation of a picosecond ultraviolet laser beam in water, sufficiently intense to cause stimulated Raman scattering (SRS), nonlinear focusing, pump-Stokes nonlinear coupling, and photoexcitation, was characterized in experiments and simulations. Pump and SRS Stokes pulse energies were measured, and pump beam profiles were imaged at propagation distances up to 100 cm for a range of laser power below and above self-focusing critical power. Simulations with conduction band excitation energy UCB=9.5eV, effective electron mass meff=0.2me, Kerr nonlinear refractive index n2=5×10-16cm2/W, and index contribution due to SRS susceptibility n2r=1.7×10-16cm2/W produced the best agreement with experimental data.

17.
Mar Drugs ; 18(2)2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31991544

RESUMO

In the current study, an NMR spectroscopic pattern-based procedure for probing scalarane derivatives was performed and four new 24-homoscalaranes, lendenfeldaranes A-D (1- 4), along with three known compounds, 12α-acetoxy-22-hydroxy-24-methyl-24-oxoscalar-16-en- 25-al (5), felixin F (6), and 24-methyl-12,24,25-trioxoscalar-16-en-22-oic acid (7) were isolated from the sponge Lendenfeldia sp. The structures of scalaranes 1-7 were elucidated on the basis of spectroscopic analysis. Scalaranes 1-7 were further evaluated for their cytotoxicity toward a series of human cancer cell lines and the results suggested that 5 and 7 dominated in the anti- proliferative activity of the extract. The 18-aldehyde functionality was found to play a key role in their activity.


Assuntos
Proliferação de Células/efeitos dos fármacos , Poríferos/química , Sesterterpenos/farmacologia , Animais , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Sesterterpenos/química , Sesterterpenos/isolamento & purificação
18.
Molecules ; 25(24)2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33339239

RESUMO

In this review, 170 natural substances, including steroid, diterpenoid, sesquiterpenoid, peptide, prostaglandin, base, chlorolipid, bicyclolactone, amide, piperazine, polyketide, glycerol, benzoic acid, glycyrrhetyl amino acid, hexitol, pentanoic acid, aminoethyl ester, octadecanone, alkaloid, and a 53-kD allergenic component from octocorals belonging to genus Dendronephthya, were listed. Some of these compounds displayed potential bioactivities.


Assuntos
Antozoários/metabolismo , Produtos Biológicos/química , Alérgenos/química , Alérgenos/metabolismo , Aminoácidos/química , Aminoácidos/metabolismo , Animais , Produtos Biológicos/metabolismo , Prostaglandinas/química , Prostaglandinas/metabolismo , Esteroides/química , Esteroides/metabolismo , Terpenos/química , Terpenos/metabolismo
19.
Molecules ; 25(6)2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32204524

RESUMO

Five 8,17-epoxybriaranes, including three new compounds-briarenols I-K (1-3), along with two known analogues, briaexcavatolide P (4) and briaexcavatin P (5), were isolated from the octocoral Briareum excavatum. The structures of briaranes 1-3 were elucidated by spectroscopic methods, including 1D and 2D NMR studies and (+)-HRESIMS. Briarane 4 exerted inhibition effects on inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) release from RAW 264.7.


Assuntos
Antozoários/química , Anti-Inflamatórios/farmacologia , Ciclo-Oxigenase 2/metabolismo , Diterpenos/farmacologia , Óxido Nítrico Sintase Tipo II/metabolismo , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Diterpenos/química , Diterpenos/isolamento & purificação , Regulação para Baixo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Camundongos , Estrutura Molecular , Células RAW 264.7
20.
Mar Drugs ; 17(9)2019 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-31540107

RESUMO

Three new 8-hydroxybriaranes-fragilides R-T (1-3) were obtained from a sea whip gorgonian coral Junceella fragilis. The structures of briaranes 1-3 were elucidated by using spectroscopic methods, including 1D (1H and 13C NMR), 2D (COSY, HSQC, HMBC, and NOESY experiments) NMR studies, and (+)-HRESIMS. Fragilides S and T (2 and 3) are the only briaranes known to possess 8α-hydroxy and 17ß-methyl groups, respectively. Briarane 2 exerted an inhibition effect on iNOS release from RAW264.7; a macrophage cell line that originated from a mouse monocyte macrophage, stimulated with lipopolysaccharides.


Assuntos
Antozoários/química , Anti-Inflamatórios/farmacologia , Diterpenos/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Diterpenos/química , Diterpenos/isolamento & purificação , Camundongos , Estrutura Molecular , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/metabolismo , Espectroscopia de Prótons por Ressonância Magnética , Células RAW 264.7 , Relação Estrutura-Atividade
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