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1.
Nat Chem Biol ; 19(12): 1513-1523, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37653169

RESUMO

The cullin-RING ubiquitin ligase (CRL) network comprises over 300 unique complexes that switch from inactive to activated conformations upon site-specific cullin modification by the ubiquitin-like protein NEDD8. Assessing cellular repertoires of activated CRL complexes is critical for understanding eukaryotic regulation. However, probes surveying networks controlled by site-specific ubiquitin-like protein modifications are lacking. We developed a synthetic antibody recognizing the active conformation of NEDD8-linked cullins. Implementing the probe to profile cellular networks of activated CUL1-, CUL2-, CUL3- and CUL4-containing E3s revealed the complexes responding to stimuli. Profiling several cell types showed their baseline neddylated CRL repertoires vary, and prime efficiency of targeted protein degradation. Our probe also unveiled differential rewiring of CRL networks across distinct primary cell activation pathways. Thus, conformation-specific probes can permit nonenzymatic activity-based profiling across a system of numerous multiprotein complexes, which in the case of neddylated CRLs reveals widespread regulation and could facilitate the development of degrader drugs.


Assuntos
Proteínas Culina , Ubiquitina-Proteína Ligases , Proteínas Culina/genética , Ubiquitinação , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina/metabolismo , Ubiquitinas/metabolismo , Proteína NEDD8/metabolismo
2.
PLoS Biol ; 20(3): e3001548, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35239649

RESUMO

Commitment to cell division at the end of G1 phase, termed Start in the budding yeast Saccharomyces cerevisiae, is strongly influenced by nutrient availability. To identify new dominant activators of Start that might operate under different nutrient conditions, we screened a genome-wide ORF overexpression library for genes that bypass a Start arrest caused by absence of the G1 cyclin Cln3 and the transcriptional activator Bck2. We recovered a hypothetical gene YLR053c, renamed NRS1 for Nitrogen-Responsive Start regulator 1, which encodes a poorly characterized 108 amino acid microprotein. Endogenous Nrs1 was nuclear-localized, restricted to poor nitrogen conditions, induced upon TORC1 inhibition, and cell cycle-regulated with a peak at Start. NRS1 interacted genetically with SWI4 and SWI6, which encode subunits of the main G1/S transcription factor complex SBF. Correspondingly, Nrs1 physically interacted with Swi4 and Swi6 and was localized to G1/S promoter DNA. Nrs1 exhibited inherent transactivation activity, and fusion of Nrs1 to the SBF inhibitor Whi5 was sufficient to suppress other Start defects. Nrs1 appears to be a recently evolved microprotein that rewires the G1/S transcriptional machinery under poor nitrogen conditions.


Assuntos
Fase G1/genética , Regulação Fúngica da Expressão Gênica , Nitrogênio/metabolismo , Fase S/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Sequência de Aminoácidos , Divisão Celular/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Immunoblotting , Ligação Proteica , RNA-Seq/métodos , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Homologia de Sequência de Aminoácidos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
3.
Opt Express ; 32(4): 6011-6024, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38439314

RESUMO

Monitoring the temperature distribution within a local environment at the micro and nanoscale is vital as many processes are solely thermal. Various thermometric techniques have been explored in the community, and out of these, fluorescent nano/micro particle-based mechanisms are accepted widely (fluorescence intensity ratio (FIR) techniques, where the ratio of populations in two consecutive energy levels is compared with Boltzmann distribution). We describe a new technique to account for the temperature rise near an illuminated upconverting particle (UCP) using wavefront imaging, which is more sensitive than the conventional thermometric techniques on the microscale. We rely on a thermo-optical phase microscopic technique by reconstructing the wavefront of emission from an upconverting particle using a Shack-Hartmann wavefront sensor. The wavefront maps the local phase distribution, which is an indicator of the surroundings' optical parameters, particularly the suspended medium's temperature-induced refractive index in the presence of convection currents. We describe how these extracted phase values can provide information about the optical heating due to the particle and hence its local environment along the direction of the emission. Our findings demonstrate the detection of a minimum temperature rise of 0.23 K, while the FIR methods indicate a minimum of 0.3 K rise. This technique is used to study the temperature increase in the backscattered direction for an upconverting particle illuminated on pump resonance. We also estimate the Soret coefficient for an upconverting particle optically trapped on pump resonance and experiencing anisotropic heating across the body.

4.
J Shoulder Elbow Surg ; 33(8): e415-e421, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38734126

RESUMO

BACKGROUND: Physical therapy (PT) is a described first-line treatment option for glenohumeral arthritis, but its efficacy for treating this spectrum of disease is not well understood. The purpose of this study is to evaluate the opinions of expert providers-orthopedic surgeons and physical therapists-regarding the utility of PT in treating glenohumeral arthritis in different stages of radiographic severity. Our goal is to identify areas of interprofessional majority agreement as well as areas without agreement that warrant further investigation. METHODS: A 35-question survey was created and distributed via email to members of the American Shoulder and Elbow Surgeons and the American Society of Shoulder and Elbow Therapists, collecting information on demographics, professional experience, and the perceived benefit of PT for patients with different stages of glenohumeral arthritis based on radiographic severity. Survey responses were analyzed for inter-professional differences in distribution of answer choices as well as for majority agreement statements. Items with >50% agreement from a professional group were considered statements of majority agreement. RESULTS: One hundred and ninety surgeons and 39 physical therapists completed the survey. Surgeons and therapists demonstrated different distribution of answer choices in 25 of the 29 nondemographic related questions (86%). Surgeons and therapists reached the same majority statement in 8 items (28%) and reached disagreeing majority statements in 4 items (14%). They agreed on the benefits of PT for mild arthritis, the benefits of corticosteroid injections, the frequency of strengthening exercises, and that PT failure should not be required for surgical approval in patients with severe arthritis. They disagreed on the whether PT exacerbates symptoms in patients with moderate arthritis, and whether preoperative PT influences postoperative outcomes. CONCLUSION: Both surgeons and therapists agreed that PT may be less beneficial for patients with more advanced radiographic arthritis and that PT failure should not be required for insurance approval for surgical intervention in patients with severe glenohumeral arthritis. Further research is needed to determine the efficacy of PT for patients with moderate arthritis as well as the utility of preoperative PT for improving postoperative outcomes.


Assuntos
Artrite , Modalidades de Fisioterapia , Articulação do Ombro , Humanos , Articulação do Ombro/cirurgia , Artrite/terapia , Masculino , Feminino , Inquéritos e Questionários , Fisioterapeutas , Atitude do Pessoal de Saúde , Cirurgiões Ortopédicos , Resultado do Tratamento , Pessoa de Meia-Idade
5.
Molecules ; 29(13)2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38999160

RESUMO

Chemically modified mandua starch was successfully synthesized and applied to coat mesalamine-loaded matrix tablets. The coating material was an aqueous dispersion of mandua starch modified by sodium trimetaphosphate and sodium tripolyphosphate. To investigate the colon-targeting release competence, chemically modified mandua starch film-coated mesalamine tablets were produced using the wet granulation method followed by dip coating. The effect of the coating on the colon-targeted release of the resultant delivery system was inspected in healthy human volunteers and rabbits using roentgenography. The results show that drug release was controlled when the coating level was 10% w/w. The release percentage in the upper gastric phase (pH 1.2, simulated gastric fluid) was less than 6% and reached up to 59.51% w/w after 14 h in simulated colonic fluid. In addition to in vivo roentgenographic studies in healthy rabbits, human volunteer studies proved the colon targeting efficiency of the formulation. These results clearly demonstrated that chemically modified mandua starch has high effectiveness as a novel aqueous coating material for controlled release or colon targeting.


Assuntos
Liberação Controlada de Fármacos , Mesalamina , Amido , Comprimidos , Mesalamina/química , Mesalamina/farmacocinética , Coelhos , Amido/química , Animais , Humanos , Concentração de Íons de Hidrogênio , Fosforilação , Preparações de Ação Retardada/química , Colo/metabolismo
6.
J Minim Access Surg ; 20(1): 89-95, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38240384

RESUMO

INTRODUCTION: The most dreaded complication during laparoscopic cholecystectomy still remains to be injury to the common bile duct. The primary cause for bile duct injury during LC is misinterpretation of the biliary anatomy. Intra-operative cholangiography was introduced as a means of reducing the chances of biliary injury, done using Fluoroscopic imaging or Near-infrared fluorescence imaging method. NIRF is one of the most popular imaging methods in biomedical sciences. Indocyanine Green is sterile and water soluble which completely binds to albumin and is excreted in bile. PATIENTS AND METHODS: This prospective study was conducted among 70 patients between July 2020 and December 2021. Subjects were administered 5mg of ICG dye pre-operatively and procedure performed using Karl Storz HD image S1 system with a D-light P light source for NIRF imaging. RESULTS: The average duration of surgery was 58.10 minutes. After calot's dissection, the CBD was visualized in 88.71 % patients, with a mean time to visualization at 26.33 minutes. The cystic duct was visualized in 87.3% cases with a mean time of visualization of 32.10 minutes. The hepatic duct was visualized in 28.57% and the hepatic duct-CBD confluence was visualized in 34.28% patients. CONCLUSION: Near infrared imaging based intra-operative cholangiography, using Indocyanine Green dye, during Lap. Cholecystectomy is an easy, useful and inexpensive method of visualizing the biliary ductal anatomy.

7.
Epilepsy Behav ; 148: 109465, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37844441

RESUMO

PURPOSE: Benign Epilepsy with Centro-Temporal Spikes (BECTS) is a pediatric epilepsy with typically good seizure control. Although BECTS may increase patients' risk of developing neurological comorbidities, their clinical care and short-term outcomes are poorly quantified. METHODS: We retrospectively assessed adherence to National Institute for Health and Care Excellence (NICE) guidelines relating to specialist referral, electroencephalogram (EEG) conduct and annual review in the care of patients with BECTS, and measured their seizure, neurodevelopmental and learning outcomes at three years post-diagnosis. RESULTS: Across ten centers in England, we identified 124 patients (74 male) diagnosed with BECTS between 2015 and 2017. Patients had a mean age at diagnosis of 8.0 (95% CI = 7.6-8.4) years. 24/95 (25%) patients were seen by a specialist within two weeks of presentation; 59/100 (59%) received an EEG within two weeks of request; and 59/114 (52%) were reviewed annually. At three years post-diagnosis, 32/114 (28%) experienced ongoing seizures; 26/114 (23%) had reported poor school progress; 15/114 (13%) were diagnosed with a neurodevelopmental disorder (six autism spectrum disorder, six attention-deficit/hyperactivity disorder); and 10/114 (8.8%) were diagnosed with a learning difficulty (three processing deficit, three dyslexia). Center-level random effects models estimated neurodevelopmental diagnoses in 9% (95% CI: 2-16%) of patients and learning difficulty diagnoses in 7% (95% CI: 2-12%). CONCLUSIONS: In this multicenter work, we found variable adherence to NICE guidelines in the care of patients with BECTS and identified a notable level of neurological comorbidity. Patients with BECTS may benefit from enhanced cognitive and behavioral assessment and monitoring.


Assuntos
Transtorno do Espectro Autista , Epilepsia Rolândica , Humanos , Criança , Masculino , Epilepsia Rolândica/diagnóstico , Epilepsia Rolândica/epidemiologia , Epilepsia Rolândica/psicologia , Estudos Retrospectivos , Transtorno do Espectro Autista/complicações , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/epidemiologia , Convulsões , Eletroencefalografia
8.
Phys Chem Chem Phys ; 25(32): 21736-21747, 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37552204

RESUMO

A large power factor and ultralow lattice thermal conductivity in 2D-monolayers of AuX (X = Cu and Ag) are achieved via first principles calculations. Low phonon frequency, small Debye temperature and high Gruneisen parameter limit the intrinsic thermal conductivity of both the studied materials. An ultra-low lattice thermal conductivity of 0.13 (0.30) W m-1 K-1 and 0.66 (1.59) W m-1 K-1 is obtained for unstrained AuCu and AuAg monolayers, respectively, at 700 (300) K, which further reduces to 0.04 (0.09) and 0.26 (0.63) W m-1 K-1 at 6% biaxial tensile strain. Such values of thermal conductivity are lower than the critical thermal conductivity for the state-of-art thermoelectric materials (kl < 2 W m-1 K-1). The peak values of ZT for unstrained monolayers are 2.20 and 1.40, which enhances to 3.61 and 2.91 at 6% strain for AuCu and AuAg monolayers, respectively. Interestingly pudding-mold band textures are found to be responsible for this unusual thermoelectric behaviour. The stability concerns (chemical/dynamic/mechanical) of these monolayers are ensured to stimulate experimental determinations for novel synthesis and possible applications.

9.
Childs Nerv Syst ; 39(2): 497-503, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35925382

RESUMO

Hypothalamic hamartomata (HH) not only are usually associated with drug-resistant epilepsy but can also cause precocious puberty and developmental delay. Gelastic seizures are the most common type of seizures. Magnetic resonance image (MRI)-guided laser interstitial thermal therapy (LiTT) is a technique whereby a laser fibre is stereotactically implanted into a target lesion and heat is used to ablate whilst tissue temperature is monitored using MRI thermography. MRI-guided LiTT has proven to be an effective and safe method to treat HH. To use the LiTT system, highly accurate stereotactic fibre implantation is required. This can be achieved by the use of frame-based or frameless neuronavigation techniques. However, these techniques generally involve rigid head immobilisation using cranial pin fixation. Patients need sufficient skull thickness to safely secure the pins and sufficient skull rigidity to prevent deformation. Hence, most of the clinical reports on the use of LiTT for children describe patients aged 2 years or older. We report a novel and practical technique of using a paste cast helmet to securely place a stereotactic frame in a 5-month-old infant with HH and drug-resistant epilepsy that allowed the successful application of MRI-guided LiTT.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsias Parciais , Hamartoma , Terapia a Laser , Criança , Humanos , Lactente , Convulsões/cirurgia , Epilepsias Parciais/cirurgia , Hamartoma/cirurgia , Epilepsia Resistente a Medicamentos/cirurgia , Terapia a Laser/métodos , Imageamento por Ressonância Magnética/métodos
10.
Pain Med ; 23(7): 1266-1271, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34850180

RESUMO

OBJECTIVE: Using stringent inclusion criteria, a double-blinded study protocol, and fluoroscopically guided injections, we compare intra-articular sacroiliac joint platelet-rich plasma injections with intra-articular steroids. DESIGN: Double-blind, randomized controlled trial. SETTING: Two large university-based interdisciplinary spine centers. SUBJECTS: A total of 26 patients with a positive diagnostic block (>80% relief). METHODS: Subjects who had a positive diagnostic block were randomized to undergo either a fluoroscopically guided intra-articular injection of steroid or a platelet-rich plasma injection. Follow-up was at 1 month, 3 months, and 6 months. Outcomes included level of pain, as indicated on a 0- to 100-mm numeric pain rating scale, and functional disability score, obtained via the Oswestry Disability Index (ODI). RESULTS: At 1, 3, and 6 months, both groups improved; however, subjects who received steroid injections reported lower pain scores than did subjects who received platelet-rich plasma. Using categorical data, we observed significantly more responders (defined as pain scores that improved by 50% or more from baseline) at 1 and 3 months in the group who received steroids than in the group who received platelet-rich plasma. CONCLUSION: Although both groups showed improvements in pain and function, the steroid group had significantly greater response and significantly more responders than did the platelet-rich plasma group.


Assuntos
Dor Lombar , Plasma Rico em Plaquetas , Corticosteroides/uso terapêutico , Artralgia , Método Duplo-Cego , Humanos , Injeções Intra-Articulares/métodos , Dor Lombar/diagnóstico , Dor Lombar/tratamento farmacológico , Dor Pélvica , Articulação Sacroilíaca , Esteroides , Resultado do Tratamento
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