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1.
Proc Natl Acad Sci U S A ; 118(2)2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33376205

RESUMO

The Aster proteins (encoded by the Gramd1a-c genes) contain a ligand-binding fold structurally similar to a START domain and mediate nonvesicular plasma membrane (PM) to endoplasmic reticulum (ER) cholesterol transport. In an effort to develop small molecule modulators of Asters, we identified 20α-hydroxycholesterol (HC) and U18666A as lead compounds. Unfortunately, both 20α-HC and U18666A target other sterol homeostatic proteins, limiting their utility. 20α-HC inhibits sterol regulatory element-binding protein 2 (SREBP2) processing, and U18666A is an inhibitor of the vesicular trafficking protein Niemann-Pick C1 (NPC1). To develop potent and selective Aster inhibitors, we synthesized a series of compounds by modifying 20α-HC and U18666A. Among these, AI (Aster inhibitor)-1l, which has a longer side chain than 20α-HC, selectively bound to Aster-C. The crystal structure of Aster-C in complex with AI-1l suggests that sequence and flexibility differences in the loop that gates the binding cavity may account for the ligand specificity for Aster C. We further identified the U18666A analog AI-3d as a potent inhibitor of all three Aster proteins. AI-3d blocks the ability of Asters to bind and transfer cholesterol in vitro and in cells. Importantly, AI-3d also inhibits the movement of low-density lipoprotein (LDL) cholesterol to the ER, although AI-3d does not block NPC1. This finding positions the nonvesicular Aster pathway downstream of NPC1-dependent vesicular transport in the movement of LDL cholesterol to the ER. Selective Aster inhibitors represent useful chemical tools to distinguish vesicular and nonvesicular sterol transport mechanisms in mammalian cells.


Assuntos
Transporte Biológico/efeitos dos fármacos , Glicoproteínas de Membrana/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Androstenos/farmacologia , Animais , Células CHO , Proteínas de Transporte/metabolismo , Membrana Celular/metabolismo , Colesterol/metabolismo , LDL-Colesterol/metabolismo , Cricetulus , Retículo Endoplasmático/metabolismo , Humanos , Hidroxicolesteróis/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana/fisiologia , Proteína C1 de Niemann-Pick/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , Esteróis/metabolismo
2.
Neuromodulation ; 27(5): 805-811, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38323974

RESUMO

INTRODUCTION: Neuromodulation represents one of the more advanced tools in the armamentarium of pain physicians. To optimize neuromodulation patient selection and management, an institutional interdisciplinary neuromodulation committee was created at each of two academic medical centers (University of California Davis [UCD] and Stanford University). The committee aims to collaboratively optimize neuromodulation candidates, to assess and minimize medical and psychologic risks, and to select the best device given a patient's pain condition. In this study, we present the methods and outcome data of the Neuromodulation Committee at the two institutions. MATERIALS AND METHODS: After institutional review board approval, we included all adult patients who were evaluated by the Neuromodulation Committee between 2017 and 2020 at two academic pain clinics. Patients with insufficient data were excluded from the study. A retrospective chart review was completed on 385 UCD and Stanford University patient committee reviews. Data collected from the chart review included demographics (age, sex), committee meeting results (proceed with trial/implant or decline), trial success, and implant rate. RESULTS: Of the 385 patients screened, the committees recommended proceeding with an implantable device (peripheral and neuraxial) in 337 patients (87.5%). Of the 278 patients recommended for neuraxial neuromodulation, 131 underwent trials with percutaneous leads (47.1%). Trials were successful (causing a ≥50% reduction in self-reported pain or improved function) in 108 patients (82.4%). The institutions completed 87 implants of 131 trials, representing a trial-to-permanent ratio of 66.4%. CONCLUSIONS: The Neuromodulation Committee aims to identify optimal patients for neuromodulation, address procedural challenges, decrease adverse events, provide educational context for trainees, and improve patient-related outcomes. Patients who were recommended for neuromodulation and subsequently underwent intervention had high trial success rates for dorsal root ganglion stimulation and spinal cord stimulation. The findings indicate that such an approach can lead to neuromodulation success, especially at academic centers, by combining the expertise of both medical and psychologic professionals.


Assuntos
Manejo da Dor , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Adulto , Manejo da Dor/métodos , Resultado do Tratamento , Seleção de Pacientes , Terapia por Estimulação Elétrica/métodos , Terapia por Estimulação Elétrica/instrumentação , Centros Médicos Acadêmicos
3.
J Biol Chem ; 298(2): 101464, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34864059

RESUMO

Wall teichoic acid (WTA) polymers are covalently affixed to the Gram-positive bacterial cell wall and have important functions in cell elongation, cell morphology, biofilm formation, and ß-lactam antibiotic resistance. The first committed step in WTA biosynthesis is catalyzed by the TagA glycosyltransferase (also called TarA), a peripheral membrane protein that produces the conserved linkage unit, which joins WTA to the cell wall peptidoglycan. TagA contains a conserved GT26 core domain followed by a C-terminal polypeptide tail that is important for catalysis and membrane binding. Here, we report the crystal structure of the Thermoanaerobacter italicus TagA enzyme bound to UDP-N-acetyl-d-mannosamine, revealing the molecular basis of substrate binding. Native MS experiments support the model that only monomeric TagA is enzymatically active and that it is stabilized by membrane binding. Molecular dynamics simulations and enzyme activity measurements indicate that the C-terminal polypeptide tail facilitates catalysis by encapsulating the UDP-N-acetyl-d-mannosamine substrate, presenting three highly conserved arginine residues to the active site that are important for catalysis (R214, R221, and R224). From these data, we present a mechanistic model of catalysis that ascribes functions for these residues. This work could facilitate the development of new antimicrobial compounds that disrupt WTA biosynthesis in pathogenic bacteria.


Assuntos
Proteínas de Bactérias , Glicosiltransferases , Lipoproteínas , Staphylococcus aureus , Ácidos Teicoicos , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Parede Celular/metabolismo , Glicosiltransferases/química , Glicosiltransferases/metabolismo , Lipoproteínas/química , Lipoproteínas/metabolismo , Staphylococcus aureus/metabolismo , Especificidade por Substrato , Ácidos Teicoicos/química , Ácidos Teicoicos/metabolismo , Difosfato de Uridina/metabolismo
4.
Neuromodulation ; 26(7): 1381-1386, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35570148

RESUMO

OBJECTIVE: This study evaluates the use of a three-dimensional virtual reality spinal cord stimulator (SCS) training system to enhance trainee confidence and technical proficiency with interlaminar epidural access and SCS placement. MATERIALS AND METHODS: A total of 14 trainees comprising pain fellows and residents were recruited. Experience and confidence levels were established through pre- and postsurveys. Each trainee performed two sessions placing SCS leads using the training device. In between attempts, a standardized teaching session was performed with the simulator. Performance during each attempt was assessed through objective measures such as needle angle and an evaluation rubric Pain Procedure Rating System (PaPRS). Statistical analysis was performed through paired sample t-test to evaluate a single group between separate trials, whereas unpaired t-test was used to assess the difference between the two groups at baseline or within a single trial. RESULTS: Participants had statistically significant improvements in their ability to safely access the epidural space (57.1% improving to 100%, p < 0.01) and to effectively drive percutaneous leads to the target level (7.1% improving to 71.4%, p < 0.001). The mean confidence levels improved by 71.4% for interlaminar epidural access (p < 0.001) and 306% for SCS placement (p < 0.001). The mean procedural efficiency (total procedure time) improved by 43.2% (p < 0.001). The PaPRS total score increased by an average of 73.3% (p < 0.001). CONCLUSIONS: Virtually simulated neuromodulation training is a viable and effective method of augmenting neuromodulation education. Such didactics are options vital for neuromodulation training, given variable exposure during residency and fellowship.


Assuntos
Internato e Residência , Realidade Virtual , Humanos , Medula Espinal , Dor , Simulação por Computador
5.
Clin Immunol ; 245: 109143, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36191738

RESUMO

BACKGROUND: New therapeutic strategies for juvenile idiopathic arthritis (JIA) have evolved within the past ten years, and as a result, an update of the 2011 recommendations of the German management guidelines was initiated. METHODS: A systemic literature review was performed, overarching principles were proposed and pre-selected via an online survey followed by two multidisciplinary consensus conferences. Pharmacological and non-pharmacological treatments were discussed, statements were proposed and ultimately agreed upon by nominal group technique (NGT). RESULTS: 12 overarching therapeutic principles, as well as 9 recommendations on pharmacological and 5 on non-pharmacological treatments for JIA were agreed upon. CONCLUSION: This report summarizes the recent update of the interdisciplinary, consensus-based German guidelines on the management of JIA. The multi- and interdisciplinary participation of all caregivers was central for this patient-focused update. With these guidelines, physicians can choose an evidence-based approach, which allows better tailored treatment in this vulnerable cohort of children and adolescents.


Assuntos
Artrite Juvenil , Adolescente , Criança , Humanos , Artrite Juvenil/tratamento farmacológico , Consenso , Deficiências do Desenvolvimento
6.
Small ; 18(12): e2106524, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35072348

RESUMO

Lipid droplets (LDs) are ubiquitous, cytoplasmic fat storage organelles that originate from the endoplasmic reticulum (ER) membrane. They are composed of a core of neutral lipids surrounded by a phospholipid monolayer. Proteins embedded into this monolayer membrane adopt a monotopic topology and are crucial for regulated lipid storage and consumption. A key question is, which collective properties of protein-intrinsic and lipid-mediated features determine spatio-temporal protein partitioning between phospholipid bilayer and LD monolayer membranes. To address this question, a freestanding phospholipid bilayer with physiological lipidic composition is produced using microfluidics and micrometer-sized LDs are dispersed around the bilayer that spontaneously insert into the bilayer. Using confocal microscopy, the 3D geometry of the reconstituted LDs is determined with high spatial resolution. The micrometer-sized bilayer-embedded LDs present a characteristic lens shape that obeys predictions from equilibrium wetting theory. Fluorescence recovery after photobleaching measurements reveals the existence of a phospholipid diffusion barrier at the monolayer-bilayer interface. Coarse-grained molecular dynamics simulation reveals lipid specific density distributions along the pore rim, which may rationalize the diffusion barrier. The lipid diffusion barrier between the LD covering monolayer and the bilayer may be a key phenomenon influencing protein partitioning between the ER membrane and LDs in living cells.


Assuntos
Gotículas Lipídicas , Fosfolipídeos , Membrana Celular/metabolismo , Retículo Endoplasmático/metabolismo , Gotículas Lipídicas/metabolismo , Simulação de Dinâmica Molecular , Fosfolipídeos/metabolismo
7.
Chemistry ; 28(2): e202103135, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34767667

RESUMO

The 4-anilino-6,7-ethylenedioxy-5-fluoroquinazoline scaffold is presented as a novel model system for the characterization of the weak NH⋅⋅⋅F hydrogen bonding (HB) interaction. In this scaffold, the aniline NH proton is forced into close proximity with the nearby fluorine (dH,F ∼2.0 Å, ∠∼138°), and a through-space interaction is observed by NMR spectroscopy with couplings (1h JNH,F ) of 19±1 Hz. A combination of experimental (NMR spectroscopy and X-ray crystallography) and theoretical methods (DFT calculations) were used for the characterization of this weak interaction. In particular, the effects of conformational rigidity and steric compression on coupling were investigated. This scaffold was used for the direct comparison of fluoride with methoxy as HB acceptors, and the susceptibility of the NH⋅⋅⋅F interaction to changes in electron distribution and resonance was probed by preparing a series of molecules with different electron-donating or -withdrawing groups in the positions para to the NH and F. The results support the idea that fluorine can act as a weak HB acceptor, and the HB strength can be modulated through additive and linear electronic substituent effects.


Assuntos
Fluoretos , Flúor , Eletrônica , Ligação de Hidrogênio , Conformação Molecular
8.
J Gastroenterol Hepatol ; 37(6): 1076-1082, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35261084

RESUMO

BACKGROUND AND AIM: The main disadvantage of plastic stents is the high rate of stent occlusion. The usual replacement interval of biliary plastic stents is 3 months. This study aimed to investigate if a shorter interval of 6-8 weeks impacts the median premature exchange rate (mPER) in benign and malignant biliary strictures. METHODS: All cases with endoscopic retrograde cholangiopancreatography (ERCP) and plastic stent placement were retrospectively analyzed since establishing an elective replacement interval of every 6-8 weeks at our institution and mPER was determined. RESULTS: A total of 3979 ERCPs (1199 patients) were analyzed, including 1262 (31.7%) malignant and 2717 (68.3%) benign cases, respectively. The median stent patency (mSP) was 41 days (range 14-120) for scheduled stent exchanges, whereas it was 17 days (1-75) for prematurely exchanged stents. The mPER was significantly higher for malignant (28.1%, 35-50%) compared with benign strictures (15.2%, 10-28%), P < 0.0001, respectively. mSP was significantly shorter in cases with only one stent (34 days [1-87] vs 41 days [1-120]) and in cases with only a 7-Fr stent (28 days [2-79]) compared with a larger stent (34 days [1-87], P = 0.001). Correspondingly, mPER was significantly higher in cases with only one stent (23% vs 16.2%, P < 0.0001) and only a 7-Fr stent (31.3% vs 22.4%, P = 0.03). CONCLUSION: A shorter replacement interval does not seem to lead to a clinically meaningful reduction of mPER in benign and malignant strictures. Large stents and multiple stenting should be favored as possible.


Assuntos
Colestase , Colangiopancreatografia Retrógrada Endoscópica , Colestase/diagnóstico por imagem , Colestase/etiologia , Colestase/cirurgia , Constrição Patológica , Humanos , Plásticos , Estudos Retrospectivos , Stents/efeitos adversos , Resultado do Tratamento
9.
Ecotoxicol Environ Saf ; 241: 113838, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36068762

RESUMO

Perfluorooctane sulfonic acid (PFOS) is a ubiquitous and persistent contaminant in aquatic ecosystems. Chronic toxicity information for aquatic organisms is limited, therefore we conducted chronic PFOS toxicity tests for four model organisms commonly used for freshwater toxicology assays: Chironomus dilutus (midge), Ceriodaphnia dubia (water flea), Hyalella azteca (amphipod) and Danio rerio (zebrafish). The 16-day survival test with C. dilutus resulted in the lowest PFOS exposure concentrations to cause significant impacts, with reduced survival at 1 µg/L, a LC50 of 7.5 µg/L, and a growth EC10 of 1.5 µg/L. D. rerio was the next most sensitive species, with a 30-day LC50 of 490 µg/L and reduced growth at 260 µg/L. Effects for C. dubia and H. azteca occurred at concentrations a thousand-fold higher than for C. dilutus. H. azteca had a 42-day LC50 of 15 mg/L, an EC50 of 3.8 mg/L for reproduction (neonates per female) and an EC50 of 4.7 mg/L for growth. C. dubia was similarly tolerant of PFOS, with a 6-day LC50 of 20 mg/L for survival and an EC50 of 7 mg/L for reproduction (neonates per adult). H. azteca, C. dubia, and, to a lesser extent, D. rerio, appear tolerant of PFOS concentrations typically found in the environment. However, in agreement with previous studies, C. dilutus was particularly sensitive to PFOS exposure, with lethal and sublethal effects occurring at concentration levels present at highly contaminated sites.


Assuntos
Anfípodes , Chironomidae , Cladocera , Poluentes Químicos da Água , Ácidos Alcanossulfônicos , Animais , Ecossistema , Feminino , Fluorocarbonos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra
10.
Anesth Analg ; 132(3): 798-806, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-32618627

RESUMO

BACKGROUND: Perioperative pediatric anxiety is common and can have a negative psychological impact on children undergoing surgery and anesthesia. Studies have shown an incidence of anxiety at induction of up to 50%. Audiovisual distraction, including virtual reality (VR), is a noninvasive, nonpharmacological modality that may reduce perioperative anxiety. The goal of this study was to determine whether immersive audiovisual distraction with a VR headset during induction of general anesthesia (GA) in pediatric patients reduced preoperative anxiety. METHODS: In this randomized-controlled, parallel-group study, 71 children 5-12 years of age scheduled for elective surgery with GA were randomly allocated to a VR group or a non-VR (No VR) control group. VR group patients underwent audiovisual distraction with a VR headset during induction in the operating room, whereas the control group received no audiovisual distraction. The primary outcome was the Modified Yale Preoperative Anxiety Scale (mYPAS), which was measured at 3 time points to assess patient anxiety: in the preoperative holding area before randomization, on entering the operating room, and during induction of GA. The primary outcome was analyzed using univariate analysis and a linear mixed-effects model. Secondary outcomes included postinduction parental anxiety measured by the State-Trait Anxiety Inventory, pediatric induction compliance, and parental satisfaction. RESULTS: Average patient age was 8.0 ± 2.3 years (mean ± standard deviation [SD]), and 51.4% of patients were female. Baseline variables were not substantially different between the VR group (33 patients) and the No VR group (37 patients). No patients received preoperative anxiolytic medication. Baseline mYPAS scores were not different between the groups, with scores of 28.3 (23.3-28.3) (median [interquartile range {IQR}]) in both. The change in mYPAS scores from baseline to time of induction was significantly lower in the VR group versus control group (0.0 [0.0-5.0] vs 13.3 [5.0-26.7]; P < .0001). In the mixed-effects model, the VR group had an estimated 6.0-point lower mYPAS score (95% confidence interval [CI], 0.7-11.3; P = .03) at room entry than the No VR group, and 14.5-point lower score (95% CI, 9.3-19.8; P < .0001) at induction versus control. Randomization to VR did not alter parental anxiety (0 [-2 to 2]), pediatric induction compliance (0 [0-0]), or parental satisfaction (-3 [-8 to 2]) (difference in medians [95% CI]). CONCLUSIONS: This study demonstrates a reduction in pediatric preoperative anxiety with the use of VR. Preoperative VR may be an effective noninvasive modality for anxiolysis during induction of anesthesia in children.


Assuntos
Anestesia Geral , Ansiedade/prevenção & controle , Comportamento Infantil , Cuidados Pré-Operatórios , Realidade Virtual , Fatores Etários , Anestesia Geral/efeitos adversos , Ansiedade/diagnóstico , Ansiedade/etiologia , Ansiedade/psicologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Estudos Prospectivos , São Francisco , Fatores de Tempo , Resultado do Tratamento
11.
Nature ; 510(7505): 397-401, 2014 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-24828042

RESUMO

Metabolism and ageing are intimately linked. Compared with ad libitum feeding, dietary restriction consistently extends lifespan and delays age-related diseases in evolutionarily diverse organisms. Similar conditions of nutrient limitation and genetic or pharmacological perturbations of nutrient or energy metabolism also have longevity benefits. Recently, several metabolites have been identified that modulate ageing; however, the molecular mechanisms underlying this are largely undefined. Here we show that α-ketoglutarate (α-KG), a tricarboxylic acid cycle intermediate, extends the lifespan of adult Caenorhabditis elegans. ATP synthase subunit ß is identified as a novel binding protein of α-KG using a small-molecule target identification strategy termed drug affinity responsive target stability (DARTS). The ATP synthase, also known as complex V of the mitochondrial electron transport chain, is the main cellular energy-generating machinery and is highly conserved throughout evolution. Although complete loss of mitochondrial function is detrimental, partial suppression of the electron transport chain has been shown to extend C. elegans lifespan. We show that α-KG inhibits ATP synthase and, similar to ATP synthase knockdown, inhibition by α-KG leads to reduced ATP content, decreased oxygen consumption, and increased autophagy in both C. elegans and mammalian cells. We provide evidence that the lifespan increase by α-KG requires ATP synthase subunit ß and is dependent on target of rapamycin (TOR) downstream. Endogenous α-KG levels are increased on starvation and α-KG does not extend the lifespan of dietary-restricted animals, indicating that α-KG is a key metabolite that mediates longevity by dietary restriction. Our analyses uncover new molecular links between a common metabolite, a universal cellular energy generator and dietary restriction in the regulation of organismal lifespan, thus suggesting new strategies for the prevention and treatment of ageing and age-related diseases.


Assuntos
Caenorhabditis elegans/efeitos dos fármacos , Ácidos Cetoglutáricos/farmacologia , Longevidade/fisiologia , ATPases Mitocondriais Próton-Translocadoras/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Linhagem Celular , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Células Jurkat , Longevidade/efeitos dos fármacos , Longevidade/genética , Camundongos , ATPases Mitocondriais Próton-Translocadoras/genética , Ligação Proteica
12.
Z Gastroenterol ; 58(2): 152-159, 2020 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-31863426

RESUMO

Patients with indeterminate biliary stricture frequently pose a challenge in the clinical management. Patients with malignant and potentially resectable diseases should be treated surgically as soon as possible. On the other hand, in patients with benign diseases which might be cured with medial treatment, surgery should be avoided. This review shall provide a concise overview on the diagnostic yield of currently available endoscopic methods as well as describe methods of potential relevance in the future.


Assuntos
Ductos Biliares/patologia , Colangiopancreatografia Retrógrada Endoscópica , Colestase/terapia , Constrição Patológica , Colestase/etiologia , Drenagem , Humanos
13.
Med Res Rev ; 39(3): 910-960, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30565725

RESUMO

Prostate cancer (PCa) is the second most common cause of cancer-related mortality in men in the United States. The androgen receptor (AR) and the physiological pathways it regulates are central to the initiation and progression of PCa. As a member of the nuclear steroid receptor family, it is a transcription factor with three distinct functional domains (ligand-binding domain [LBD], DNA-binding domain [DBD], and transactivation domain [TAD]) in its structure. All clinically approved drugs for PCa ultimately target the AR-LBD. Clinically active drugs that target the DBD and TAD have not yet been developed due to multiple factors. Despite these limitations, the last several years have seen a rise in the discovery of molecules that could successfully target these domains. This review aims to present and comprehensively discuss such molecules that affect AR signaling through direct or indirect interactions with the AR-TAD or the DBD. The compounds discussed here include hairpin polyamides, niclosamide, marine sponge-derived small molecules (eg, EPI compounds), mahanine, VPC compounds, JN compounds, and bromodomain and extraterminal domain inhibitors. We highlight the significant in vitro and in vivo data found for each compound and the apparent limitations and/or potential for further development of these agents as PCa therapies.


Assuntos
Receptores Androgênicos/química , Receptores Androgênicos/metabolismo , Transdução de Sinais , Animais , Ensaios Clínicos como Assunto , Progressão da Doença , Humanos , Ligantes , Domínios Proteicos
14.
J Virol ; 91(4)2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-27903801

RESUMO

Many enveloped viruses cause devastating disease in aquaculture, resulting in significant economic impact. LJ001 is a broad-spectrum antiviral compound that inhibits enveloped virus infections by specifically targeting phospholipids in the lipid bilayer via the production of singlet oxygen (1O2). This stabilizes positive curvature and decreases membrane fluidity, which inhibits virus-cell membrane fusion during viral entry. Based on data from previous mammalian studies and the requirement of light for the activation of LJ001, we hypothesized that LJ001 may be useful as a preventative and/or therapeutic agent for infections by enveloped viruses in aquaculture. Here, we report that LJ001 was more stable with a prolonged inhibitory half-life at relevant aquaculture temperatures (15°C), than in mammalian studies at 37°C. When LJ001 was preincubated with our model virus, infectious hematopoietic necrosis virus (IHNV), infectivity was significantly inhibited in vitro (using the epithelioma papulosum cyprini [EPC] fish cell line) and in vivo (using rainbow trout fry) in a dose-dependent and time-dependent manner. While horizontal transmission of IHNV in a static cohabitation challenge model was reduced by LJ001, transmission was not completely blocked at established antiviral doses. Therefore, LJ001 may be best suited as a therapeutic for aquaculture settings that include viral infections with lower virus-shedding rates than IHNV or where higher viral titers are required to initiate infection of naive fish. Importantly, our data also suggest that LJ001-inactivated IHNV elicited an innate immune response in the rainbow trout host, making LJ001 potentially useful for future vaccination approaches. IMPORTANCE: Viral diseases in aquaculture are challenging because there are few preventative measures and/or treatments. Broad-spectrum antivirals are highly sought after and studied because they target common components of viruses. In our studies, we used LJ001, a broad-spectrum antiviral compound that specifically inhibits enveloped viruses. We used the fish rhabdovirus infectious hematopoietic necrosis virus (IHNV) as a model to study aquatic enveloped virus diseases and their inhibition. We demonstrated inhibition of IHNV by LJ001 both in cell culture as well as in live fish. Additionally, we showed that LJ001 inhibited the transmission of IHNV from infected fish to healthy fish, which lays the groundwork for using LJ001 as a possible therapeutic for aquatic viruses. Our results also suggest that virus inactivated by LJ001 induces an immune response, showing potential for future preventative (e.g., vaccine) applications.


Assuntos
Antivirais/farmacologia , Doenças dos Peixes/virologia , Infecções por Rhabdoviridae/virologia , Rhabdoviridae/efeitos dos fármacos , Animais , Aquicultura , Relação Dose-Resposta a Droga , Doenças dos Peixes/tratamento farmacológico , Doenças dos Peixes/genética , Doenças dos Peixes/transmissão , Regulação da Expressão Gênica/efeitos dos fármacos , Infecções por Rhabdoviridae/tratamento farmacológico , Infecções por Rhabdoviridae/genética , Infecções por Rhabdoviridae/transmissão
15.
Endoscopy ; 50(12): 1205-1234, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30458567

RESUMO

This Position Statement from the European Society of Gastrointestinal Endoscopy (ESGE) and the European Society of Gastroenterology Nurses and Associates (ESGENA) sets standards for the reprocessing of flexible endoscopes and endoscopic devices used in gastroenterology. An expert working group of gastroenterologists, endoscopy nurses, chemists, microbiologists, and industry representatives provides updated recommendations on all aspects of reprocessing in order to maintain hygiene and infection control.


Assuntos
Desinfecção/métodos , Desinfecção/normas , Endoscópios/normas , Endoscopia Gastrointestinal/instrumentação , Contaminação de Equipamentos/prevenção & controle , Controle de Infecções/normas , Documentação/normas , Humanos , Saúde Ocupacional/normas , Esterilização/métodos , Esterilização/normas
16.
Langmuir ; 34(29): 8542-8549, 2018 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-29886739

RESUMO

Hydrophobins are a family of small-sized proteins featuring a distinct hydrophobic patch on the protein's surface, rendering them amphiphilic. This particularity allows hydrophobins to self-assemble into monolayers at any hydrophilic/hydrophobic interface. Moreover, stable pure protein bilayers can be created from two interfacial hydrophobin monolayers by contacting either their hydrophobic or their hydrophilic sides. In this study, this is achieved via a microfluidic approach, in which also the bilayers' adhesion energy can be determined. This enables us to study the origin of the adhesion of hydrophobic and hydrophilic core bilayers made from the class II hydrophobins HFBI and HFBII. Using different fluid media in this setup and introducing genetically modified variants of the HFBI molecule, the different force contributions to the adhesion of the bilayer sheets are studied. It was found that in the hydrophilic contact situation, the adhesive interaction was higher than that in the hydrophobic contact situation and could be even enhanced by reducing the contributions of electrostatic interactions. This effect indicates that the van der Waals interaction is the dominant contribution that explains the stability of the observed bilayers.

18.
J Biol Chem ; 291(27): 14146-14159, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-27226604

RESUMO

Our previous work has demonstrated an intrinsic mRNA-specific protein synthesis salvage pathway operative in glioblastoma (GBM) tumor cells that is resistant to mechanistic target of rapamycin (mTOR) inhibitors. The activation of this internal ribosome entry site (IRES)-dependent mRNA translation initiation pathway results in continued translation of critical transcripts involved in cell cycle progression in the face of global eIF-4E-mediated translation inhibition. Recently we identified compound 11 (C11), a small molecule capable of inhibiting c-MYC IRES translation as a consequence of blocking the interaction of a requisite c-MYC IRES trans-acting factor, heterogeneous nuclear ribonucleoprotein A1, with its IRES. Here we demonstrate that C11 also blocks cyclin D1 IRES-dependent initiation and demonstrates synergistic anti-GBM properties when combined with the mechanistic target of rapamycin kinase inhibitor PP242. The structure-activity relationship of C11 was investigated and resulted in the identification of IRES-J007, which displayed improved IRES-dependent initiation blockade and synergistic anti-GBM effects with PP242. Mechanistic studies with C11 and IRES-J007 revealed binding of the inhibitors within the UP1 fragment of heterogeneous nuclear ribonucleoprotein A1, and docking analysis suggested a small pocket within close proximity to RRM2 as the potential binding site. We further demonstrate that co-therapy with IRES-J007 and PP242 significantly reduces tumor growth of GBM xenografts in mice and that combined inhibitor treatments markedly reduce the mRNA translational state of cyclin D1 and c-MYC transcripts in these tumors. These data support the combined use of IRES-J007 and PP242 to achieve synergistic antitumor responses in GBM.


Assuntos
Neoplasias Encefálicas/terapia , Ciclina D1/genética , Genes myc , Glioblastoma/terapia , Sítios Internos de Entrada Ribossomal , Biossíntese de Proteínas , RNA Mensageiro/genética , Serina-Treonina Quinases TOR/antagonistas & inibidores , Animais , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Feminino , Glioblastoma/metabolismo , Xenoenxertos , Humanos , Camundongos
19.
Endoscopy ; 49(11): 1098-1106, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29036747

RESUMO

Patients should be informed about the benefits and risks of endoscopic retrograde cholangiopancreatography (ERCP)Only specially trained and competent personnel should carry out endoscope reprocessing.Manufacturers of duodenoscopes should provide detailed instructions on how to use and reprocess their equipment.In the case of modifications to their equipment, manufacturers should provide updated instructions for use.Detailed reprocessing protocols based on the manufacturer's instructions for use should clearly lay out the different reprocessing steps necessary for each endoscope model.Appropriate cleaning equipment should be used for duodenoscopes in compliance with the manufacturer's instructions for use. Only purpose-designed, endoscope type-specific, single-use cleaning brushes should be used, to ensure optimal cleaning. As soon as the endoscope is withdrawn from the patient, bedside cleaning should be performed, followed by leak testing, thorough manual cleaning steps, and automated reprocessing, in order to: · Remove debris from external and internal surfaces;. · Prevent any drying of body fluids, blood, or debris;. · Prevent any formation of biofilms.. In addition to the leak test, visual inspection of the distal end as well as regular maintenance of duodenoscopes should be performed according to the manufacturer's instructions for use, in order to detect any damage at an early stage.The entire reprocessing procedure in endoscope washer-disinfectors (EWDs) should be validated according to the European and International Standard, EN ISO 15883. Routine technical tests of EWDs should be performed according to the validation reports.Microbiological surveillance of a proportion of the department's endoscopes should be performed every 3 months, with the requirement that all endoscopes used in the unit are tested at least once a year.In the case of suspected endoscopy-related infection, the relevant device (e. g., endoscope, EWD) should be taken out of service until adequate corrective actions have been taken. Outbreaks should be managed by a multidisciplinary team, including endoscopy, hygiene, and microbiology experts, manufacturers, and regulatory bodies, according to national standards and/or laws. In the case of suspected multidrug-resistant organism (MDRO) outbreaks, close cooperation between the endoscopy unit and the clinical health provider is essential (including infection control departments and hospital hygienists).


Assuntos
Infecção Hospitalar/prevenção & controle , Descontaminação/métodos , Descontaminação/normas , Resistência a Múltiplos Medicamentos , Duodenoscópios/normas , Contaminação de Equipamentos/prevenção & controle , Infecção Hospitalar/microbiologia , Duodenoscópios/microbiologia , Humanos , Controle de Infecções/métodos
20.
Endoscopy ; 49(12): 1262-1275, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29145674

RESUMO

1 Prerequisites. The clinical service provider should obtain confirmation from the endoscope washer-disinfector (EWD) manufacturer that all endoscopes intended to be used can be reprocessed in the EWD. 2 Installation qualification. This can be performed by different parties but national guidelines should define who has the responsibilities, taking into account legal requirements. 3 Operational qualification. This should include parametric tests to verify that the EWD is working according to its specifications. 4 Performance qualification. Testing of cleaning performance, microbiological testing of routinely used endoscopes, and the quality of the final rinse water should be considered in all local guidelines. The extent of these tests depends on local requirements. According to the results of type testing performed during EWD development, other parameters can be tested if local regulatory authorities accept this. Chemical residues on endoscope surfaces should be searched for, if acceptable test methods are available. 5 Routine inspections. National guidelines should consider both technical and performance criteria. Individual risk analyses performed in the validation and requalification processes are helpful for defining appropriate test frequencies for routine inspections.


Assuntos
Desinfecção/instrumentação , Desinfecção/normas , Endoscópios/microbiologia , Reutilização de Equipamento/normas , Controle de Qualidade , Desinfecção/métodos , Documentação , Endoscópios/normas , Contaminação de Equipamentos/prevenção & controle , Guias como Assunto , Estudos de Validação como Assunto
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