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1.
Chem Sci ; 15(25): 9676-9693, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38939156

RESUMO

Study of alternating DNA GC sequences by different time-resolved spectroscopies has provided fundamental information on the interaction between UV light and DNA, a process of great biological importance. Multiple decay paths have been identified, but their interplay is still poorly understood. Here, we characterize the photophysics of GC-DNA by integrating different computational approaches, to study molecular models including up to 6 bases described at a full quantum mechanical level. Quantum dynamical simulations, exploiting a nonadiabatic linear vibronic coupling (LVC) model, coupled with molecular dynamics sampling of the initial structures of a (GC)5 DNA duplex, provide new insights into the photophysics in the sub-picosecond time-regime. They indicate a substantial population transfer, within 50 fs, from the spectroscopic states towards G → C charge transfer states involving two stacked bases (CTintra), thus explaining the ultrafast disappearance of fluorescence. This picture is consistent with that provided by quantum mechanical geometry optimizations, using time dependent-density functional theory and a polarizable continuum model, which we use to parametrize the LVC model and to map the main excited state deactivation pathways. For the first time, the infrared and excited state absorption signatures of the various states along these pathways are comprehensively mapped. The computational models suggest that the main deactivation pathways, which, according to experiment, lead to ground state recovery on the 10-50 ps time scale, involve CTintra followed by interstrand proton transfer from the neutral G to C-. Our calculations indicate that CTintra is populated to a larger extent and more rapidly in GC than in CG steps and suggest the likely involvement of monomer-like and interstrand charge transfer decay routes for isolated and less stacked CG steps. These findings underscore the importance of the DNA sequence and thermal fluctuations for the dynamics. They will also aid the interpretation of experimental results on other sequences.

2.
Nat Commun ; 15(1): 4232, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762479

RESUMO

Toll-like receptor 9 (TLR9) recognizes bacterial, viral and self DNA and play an important role in immunity and inflammation. However, the role of TLR9 in obesity is less well-studied. Here, we generate B-cell-specific Tlr9-deficient (Tlr9fl/fl/Cd19Cre+/-, KO) B6 mice and model obesity using a high-fat diet. Compared with control mice, B-cell-specific-Tlr9-deficient mice exhibited increased fat tissue inflammation, weight gain, and impaired glucose and insulin tolerance. Furthermore, the frequencies of IL-10-producing-B cells and marginal zone B cells were reduced, and those of follicular and germinal center B cells were increased. This was associated with increased frequencies of IFNγ-producing-T cells and increased follicular helper cells. In addition, gut microbiota from the KO mice induced a pro-inflammatory state leading to immunological and metabolic dysregulation when transferred to germ-free mice. Using 16 S rRNA gene sequencing, we identify altered gut microbial communities including reduced Lachnospiraceae, which may play a role in altered metabolism in KO mice. We identify an important network involving Tlr9, Irf4 and Il-10 interconnecting metabolic homeostasis, with the function of B and T cells, and gut microbiota in obesity.


Assuntos
Linfócitos B , Dieta Hiperlipídica , Disbiose , Microbioma Gastrointestinal , Inflamação , Interleucina-10 , Camundongos Knockout , Obesidade , Receptor Toll-Like 9 , Animais , Obesidade/imunologia , Obesidade/microbiologia , Obesidade/metabolismo , Disbiose/imunologia , Disbiose/microbiologia , Receptor Toll-Like 9/metabolismo , Receptor Toll-Like 9/genética , Linfócitos B/imunologia , Linfócitos B/metabolismo , Inflamação/metabolismo , Camundongos , Dieta Hiperlipídica/efeitos adversos , Interleucina-10/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Fatores Reguladores de Interferon
3.
J Med Internet Res ; 26: e49409, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38625726

RESUMO

BACKGROUND: The incidence of stroke in children is low, and pediatric stroke rehabilitation services are less developed than adult ones. Survivors of pediatric stroke have a long poststroke life expectancy and therefore have the potential to experience impairments from their stroke for many years. However, there are relatively few studies characterizing these impairments and what factors facilitate or counteract recovery. OBJECTIVE: This study aims to characterize the main barriers to and facilitators of recovery from pediatric stroke. A secondary aim was to explore whether these factors last into adulthood, whether they change, or if new factors impacting recovery emerge in adulthood. METHODS: We performed a qualitative thematic analysis based on posts from a population of participants from a UK-based online stroke community, active between 2004 and 2011. The analysis focused on users who talked about their experiences with pediatric stroke, as identified by a previous study. The posts were read by 3 authors, and factors influencing recovery from pediatric stroke were mapped into 4 areas: medical, physical, emotional, and social. Factors influencing recovery were divided into short-term and long-term factors. RESULTS: There were 425 posts relating to 52 survivors of pediatric stroke. Some survivors of stroke posted for themselves, while others were talked about by a third party (mostly parents; 31/35, 89% mothers). In total, 79% (41/52) of survivors of stroke were aged ≤18 years and 21% (11/52) were aged >18 years at the time of posting. Medical factors included comorbidities as a barrier to recovery. Medical interventions, such as speech and language therapy and physiotherapy, were also deemed useful. Exercise, particularly swimming, was deemed a facilitator. Among physical factors, fatigue and chronic pain could persist decades after a stroke, with both reported as a barrier to feeling fully recovered. Tiredness could worsen existing stroke-related impairments. Other long-standing impairments were memory loss, confusion, and dizziness. Among emotional factors, fear and uncertainty were short-term barriers, while positivity was a major facilitator in both short- and long-term recovery. Anxiety, grief, and behavioral problems hindered recovery. The social barriers were loneliness, exclusion, and hidden disabilities not being acknowledged by third parties. A good support network and third-party support facilitated recovery. Educational services were important in reintegrating survivors into society. Participants reported that worrying about losing financial support, such as disability allowances, and difficulties in obtaining travel insurance and driving licenses impacted recovery. CONCLUSIONS: The lived experience of survivors of pediatric stroke includes long-term hidden disabilities and barriers to rehabilitation. These are present in different settings, such as health care, schools, workplaces, and driving centers. Greater awareness of these issues by relevant professional groups may help ameliorate them.


Assuntos
Dor Crônica , Emoções , Adulto , Humanos , Criança , Ansiedade , Transtornos de Ansiedade , Fadiga , Reino Unido
4.
Chemotherapy ; : 1-7, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38679017

RESUMO

INTRODUCTION: As tumour response rates are increasingly demonstrated in early-phase cancer trials (EPCT), optimal patient selection and accurate prognostication are paramount. Hammersmith Score (HS), a simple prognostic index derived on routine biochemical measures (albumin <35 g/L, lactate dehydrogenase >450 IU/L, sodium <135 mmol/L), is a validated predictor of response and survival in EPCT participants. HS has not been validated in the cancer immunotherapy era. METHODS: We retrospectively analysed characteristics and outcomes of unselected referrals to our early-phase unit (12/2019-12/2022). Independent predictors for overall survival (OS) were identified from univariable and multivariable models. HS was calculated for 66 eligible trial participants and compared with the Royal Marsden Score (RMS) to predict OS. Multivariable logistic regression and C-index was used to compare predictive ability of prognostic models. RESULTS: Of 212 referrals, 147 patients were screened and 82 patients treated in EPCT. Prognostic stratification by HS identifies significant difference in median OS, and HS was confirmed as a multivariable predictor for OS (HR: HS 1 vs. 0 2.51, 95% CI: 1.01-6.24, p = 0.049; HS 2/3 vs. 0: 10.32, 95% CI: 2.15-49.62, p = 0.004; C-index 0.771) with superior multivariable predictive ability than RMS (HR: RMS 2 vs. 0/1 5.46, 95% CI: 1.12-26.57, p = 0.036; RMS 3 vs. 0/1 6.83, 95% CI: 1.15-40.53, p < 0.001; C-index 0.743). CONCLUSIONS: HS is a validated prognostic index for patients with advanced cancer treated in the context of modern EPCTs, independent of tumour burden. HS is a simple, inexpensive prognostic tool to optimise referral for EPCT.

5.
Sci Adv ; 10(12): eadj2770, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38507499

RESUMO

Sulfur degassed at volcanic arcs calls for dissolved sulfate ions (S6+) released by subduction-zone fluids, oxidizing (in association with carbon) the subarc mantle, but sulfur speciation in subduction fluids at subarc depths remains unclear. We apply electrolytic fluid thermodynamics to model the dissolution behavior of pyrite in metacarbonate sediments as a function of P, T and rock redox state up to 4.3 gigapascals and 730°C. At subarc depth and the redox conditions of the fayalite-magnetite-quartz oxygen buffer, pyrite dissolution releases oxidized sulfur in fluids by disproportionation into sulfate, bisulfite, and sulfide species. These findings indicate that oxidized, sulfur-rich carbon-oxygen-hydrogen-sulfur (COHS) fluids form within subducting slabs at depths greater than 100 kilometers independent from slab redox state and that sulfur can be more effective than the concomitantly dissolved carbon at oxidizing the mantle wedge, especially when carbonates are stable.

6.
Front Immunol ; 15: 1333967, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38482010

RESUMO

Introduction: The incidence of the autoimmune disease, type 1 diabetes (T1D), has been increasing worldwide and recent studies have shown that the gut microbiota are associated with modulating susceptibility to T1D. Toll-like receptor 5 (TLR5) recognizes bacterial flagellin and is widely expressed on many cells, including dendritic cells (DCs), which are potent antigen-presenting cells (APCs). TLR5 modulates susceptibility to obesity and alters metabolism through gut microbiota; however, little is known about the role TLR5 plays in autoimmunity, especially in T1D. Methods: To fill this knowledge gap, we generated a TLR5-deficient non-obese diabetic (NOD) mouse, an animal model of human T1D, for study. Results: We found that TLR5-deficiency led to a reduction in CD11c+ DC development in utero, prior to microbial colonization, which was maintained into adulthood. This was associated with a bias in the DC populations expressing CD103, with or without CD8α co-expression, and hyper-secretion of different cytokines, both in vitro (after stimulation) and directly ex vivo. We also found that TLR5-deficient DCs were able to promote polyclonal and islet antigen-specific CD4+ T cell proliferation and proinflammatory cytokine secretion. Interestingly, only older TLR5-deficient NOD mice had a greater risk of developing spontaneous T1D compared to wild-type mice. Discussion: In summary, our data show that TLR5 modulates DC development and enhances cytokine secretion and diabetogenic CD4+ T cell responses. Further investigation into the role of TLR5 in DC development and autoimmune diabetes may give additional insights into the pathogenesis of Type 1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1 , Animais , Humanos , Camundongos , Citocinas/metabolismo , Células Dendríticas , Suscetibilidade a Doenças/metabolismo , Camundongos Endogâmicos NOD , Receptor 5 Toll-Like/metabolismo
7.
bioRxiv ; 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38328068

RESUMO

Plasmodium falciparum pathology is driven by the accumulation of parasite-infected erythrocytes in microvessels. This process is mediated by the parasite's polymorphic erythrocyte membrane protein 1 (PfEMP1) adhesion proteins. A subset of PfEMP1 variants that bind human endothelial protein C receptor (EPCR) through their CIDRα1 domains is responsible for severe malaria pathogenesis. A longstanding question is whether individual antibodies can recognize the large repertoire of circulating PfEMP1 variants. Here, we describe two broadly reactive and binding-inhibitory human monoclonal antibodies against CIDRα1. The antibodies isolated from two different individuals exhibited a similar and consistent EPCR-binding inhibition of 34 CIDRα1 domains, representing five of the six subclasses of CIDRα1. Both antibodies inhibited EPCR binding of both recombinant full-length and native PfEMP1 proteins as well as parasite sequestration in bioengineered 3D brain microvessels under physiologically relevant flow conditions. Structural analyses of the two antibodies in complex with two different CIDRα1 antigen variants reveal similar binding mechanisms that depend on interactions with three highly conserved amino acid residues of the EPCR-binding site in CIDRα1. These broadly reactive antibodies likely represent a common mechanism of acquired immunity to severe malaria and offer novel insights for the design of a vaccine or treatment targeting severe malaria.

8.
Drug Metab Dispos ; 52(3): 153-158, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38216306

RESUMO

The administration of radiolabeled drug candidates is considered the gold standard in absorption, distribution, metabolism, and excretion studies for small-molecule drugs since it allows facile and accurate quantification of parent drug, metabolites, and total drug-related material independent of the compound structure. The choice of the position of the radiolabel, typically 14C or 3H, is critical to obtain relevant information. Sometimes, a biotransformation reaction may lead to cleavage of a part of the molecule. As a result, only the radiolabeled portion can be followed, and information on the fate of the nonlabeled metabolite may be lost. Synthesis and administration of two or more radiolabeled versions of the parent drug as a mixture or in separate studies may resolve this issue but comes with additional challenges. In this paper, we address the questions that may be considered to help make the right choice whether to use a single or multiple radiolabel approach and discuss the pros and cons of different multiple-labeling strategies that can be taken as well as alternative methods that allow the nonlabeled part of the molecule to be followed. SIGNIFICANCE STATEMENT: Radiolabeled studies are the gold standard in drug metabolism research, but molecules can undergo cleavage with loss of the label. This often results in discussions around potential use of multiple labels, which seem to be occurring with increased frequency since an increasing proportion of the small-molecule drugs are tending towards larger molecular weights. This review provides insight and decision criteria in considering a multiple-label approach as well as pros and cons of different strategies that can be followed.


Assuntos
Preparações Farmacêuticas , Humanos , Preparações Farmacêuticas/metabolismo , Taxa de Depuração Metabólica , Biotransformação
9.
Urologia ; 91(1): 199-206, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37897311

RESUMO

BACKGROUND AND AIMS: Ketamine use as a recreational drug is becoming more popular nowadays. Ketamine-induced uropathy (KIU) is a late finding observed with long-term use of ketamine. A systematic review of Ketamine-Induced Uropathy was performed to emphasise its key clinical manifestations, mechanism of action and establish an effective treatment pathway. METHODS AND RESULTS: A literature search was conducted in MEDLINE via Pubmed and Cochrane using the keywords ketamine and bladder, ketamine and uropathy, and ketamine and epidemiology. The search strategy was limited to articles published from 2000 to 2023. Both animal and human studies were included. A total of 101 papers were reviewed based on topic relevance from the title and abstracts available. While ketamine is a controlled drug in the United Kingdom (UK) and other countries, 283 ketamine-related deaths have been reported in the UK. There is no definite pathogenesis but multiple potential mechanisms that cause KIU and its related symptoms. KIU involves chronic inflammation of the bladder, ureteral wall thickening, hydronephrosis and finally, chronic renal failure. A multidisciplinary approach is paramount when managing these patients to break the vicious cycle. The mainstay of medical and surgical treatment pathways is continued abstinence to prevent symptom relapse. This review included the pathophysiology, novel medical treatments and surgical management of KIU. CONCLUSION: KIU is a rare but significantly disabling condition often seen among ketamine abusers. With the rising trend in drug addiction, KIU is expected to be more common. Unfortunately, it is a late complication in chronic ketamine abusers and is only partially reversible even with abstinence. This review discusses this rare entity's newer medical treatments and surgical options.


Assuntos
Hidronefrose , Ketamina , Insuficiência Renal Crônica , Transtornos Relacionados ao Uso de Substâncias , Humanos , Hidronefrose/induzido quimicamente , Ketamina/efeitos adversos , Insuficiência Renal Crônica/induzido quimicamente , Transtornos Relacionados ao Uso de Substâncias/complicações , Bexiga Urinária
10.
Clin Pharmacol Ther ; 115(5): 931-938, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38018358

RESUMO

A review of the use of microdoses and isotopic microtracers for clinical intravenous pharmacokinetic (i.v. PK) data provision is presented. The extent of application of the varied approaches available and the relative merits of each are highlighted with the aim of assisting practitioners in making informed decisions on the most scientifically appropriate design to adopt for any given new drug in development. It is envisaged that significant efficiencies will be realized as i.v. PK data in humans becomes more routinely available for suitable assets in early development, than has been the case prior to the last decade.


Assuntos
Tomada de Decisões , Farmacocinética , Humanos , Administração Intravenosa , Modelos Biológicos
11.
Biomedica ; 43(Sp. 1): 229-244, 2023 08 31.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-37721917

RESUMO

Introduction. The real laboratory conditions of each country, including climate, can affect the method's efficiency in analyzing a pharmacological substance. Thus, it is necessary to validate the process according to the corresponding guidelines and optimize it to ensure success and confidence in the results. Objective. The objective was to validate a methodology for fluconazole and its organic impurities quantification in raw material using high-performance liquid chromatography, with a diode array detector, under tropical climate conditions, and complying with all regulatory requirements. Materials and methods. We performed pre-validation tests of the method consisting of system adequacy, filters study, quantification limit, absence of systematic error, forced degradation studies, and solutions stability. In addition, we validated the specificity, linearity, accuracy, precision, and robustness of the system. Results. Separation of the degradation products from the analyte peaks allowed the achievement of the method's spectral purity. The solution's stability was not affected during the evaluated time (24 hours) at room temperature and under refrigeration. Linearity resulted in correlation coefficients greater than or equal to 0.999 for the evaluation and greater than or equal to 0.997 for impurities. We obtained a fluconazole recovery varying from 98 to 102% with an accuracy between 80 to 120% for impurities detection. The repeatability and reproducibility factor did not exceed a relative standard deviation of 2.0% for the evaluation and of 5.0% for the impurities, demonstrating the adequate robustness of the method. In addition, a short analysis execution time allowed the quick determination of the raw material quality. Conclusion. We demonstrated that the fluconazole quantification method validated by high-performance liquid chromatography is sufficiently selective, precise, exact, linear, and robust to generate accurate analytical results under real conditions, including the tropical climate of Colombia.


Introducción. La eficiencia de una metodología para analizar una sustancia farmacológica puede verse afectada por las condiciones reales del laboratorio de cada país, incluyendo el clima. Por esta razón, se requiere validar el método con las pautas recomendadas para ello y optimizar el proceso, para asegurar el éxito y la confianza en los resultados. Objetivo. Validar una metodología para la cuantificación simultánea del fluconazol (materia prima) y sus impurezas orgánicas mediante cromatografía líquida de alta resolución con detector de arreglo de diodos en condiciones de clima tropical y con todos los requisitos normativos. Materiales y métodos. Se hicieron pruebas previas a la validación del método: idoneidad del sistema, estudio de filtros, límite de cuantificación, ausencia del error sistemático, estudios de degradación forzada y estabilidad de las soluciones. Además, se validaron: la especificidad, la linealidad, la exactitud, la precisión y la robustez. Resultados. La pureza espectral del método se logró al obtener la separación de los productos de degradación de los picos de los analitos. La estabilidad de las soluciones no se vio afectada, en la frecuencia evaluada de 24 horas, a temperatura ambiente y de refrigeración. Se obtuvo una linealidad con coeficientes de correlación mayores o iguales a 0,999 para la valoración y mayores o iguales a 0,997 para las impurezas. La recuperación estuvo en el rango de 98 a 102,0 % de fluconazol, con una exactitud entre el 80 y el 120 % para las impurezas. El factor de repetibilidad y reproducibilidad no superó la desviación estándar relativa del 2,0 % para la valoración y, la del 5,0 %, para las impurezas, lo cual mostró una solidez adecuada del método. Además, se obtuvo un tiempo corto de ejecución del análisis, lo que permitió la rápida determinación de la calidad de la materia prima. Conclusión. Se demostró que el método de cuantificación de fluconazol, validado por cromatografía líquida de alta resolución con detector de arreglo de diodos, es lo suficientemente selectivo, preciso, exacto, lineal y robusto; además, es capaz de generar resultados analíticos veraces en condiciones de uso reales, incluyendo el clima tropical de Colombia.

12.
World J Urol ; 41(10): 2679-2684, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37668719

RESUMO

INTRODUCTION: It is important for robotic surgery to be cost-effective, especially by reducing the length of stay (LOS). Therefore, we developed a protocol for day-case robot-assisted radical prostatectomy (RARP). This study aimed to validate this as a safe practice of care and to assess the potential benefits to the hospital and patient. METHODS: In this single-centre study, all patients booked for RARP between April 2022 and October 2022 were screened for suitability for day case. All tumour types were included. Exclusion criteria were a history of complex abdominal surgeries, salvage prostatectomy, body mass index (BMI) > 35 and patient living alone or > 150 km away from the hospital. All day-case RARPs were performed as a morning case with a protocol for review throughout the day with evening discharge if mobilising independently and eating/drinking well. The primary outcome of the study was success rate of discharge home on day of surgery (DOS) with secondary outcomes of readmissions and complications. A patient questionnaire was completed at home including both visual analogue scale (VAS) for pain and satisfaction rating. RESULTS: Forty-five patients underwent day-case RARP over a 6-month period with minimum of 30 days of follow-up. 41/45 (91%) had successful DOS discharge home. The four admissions overnight were due to dizziness, low oxygen saturation, intraoperative complications and a diagnosis of COVID-19. There were no readmissions and no 30-day complications. The most common issues at home were catheter discomfort and constipation with low mean VAS pain score and low nausea reported. The overall patient satisfaction rating was very high at 4.8/5, and 97% said they would recommend to a family member. The cost saving for the hospital was 400 pounds per patient. CONCLUSION: Day-case procedure is a viable, safe and efficient pathway for appropriately selected and counselled patients undergoing RARP.


Assuntos
COVID-19 , Procedimentos Cirúrgicos Robóticos , Robótica , Masculino , Humanos , Procedimentos Cirúrgicos Robóticos/métodos , Alta do Paciente , Prostatectomia/métodos , Dor , Resultado do Tratamento
13.
J Robot Surg ; 17(6): 2697-2701, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37548820

RESUMO

Self-removal of urinary catheter as an option after robot-assisted radical prostatectomy (RARP) has never been explored in literature. We report the feasibility and outcome of the first study of this novel concept in our hospital. We conducted a prospective audit of self-TWOC (trial without catheter) in men who underwent consecutive RARP in our centre between April 2022 and September 2022. Men who had self-TWOC filled a questionnaire about the outcomes of self-TWOC. Carbon footprint and carbon offset for each hospital TWOC avoided were calculated. Of the 129 who underwent self-TWOC, 112 filled the questionnaire and were hence included in the final analysis. Self-TWOC was successful in all the 112 (100%) men in the study. 99.1% of men were satisfied with self-TWOC at home. We managed to avoid 79.6 ± 36.72 km of travel and 77 min of travel time for every self-TWOC. This also saved 85£/patient on clinic expenses and fuel cost savings of 9.87-15.99£ per patient depending on car engine size/type. The carbon footprint calculated was 20 kg CO2 assuming average engine sized diesel/petrol cars and 10 kg CO2 for an average UK petrol hybrid car. The calculated carbon offset per patient for diesel/petrol cars: 0.32£, petrol hybrid: 0.16£. Self-TWOC for 80-160 patients will save the carbon emissions equivalent to that of a passenger on a London-New York Trans-Atlantic flight. Self-TWOC is safe, affordable and is sustainable to the environment. Widespread acceptance of this practice change will be a small, but steady step towards greener health systems across the world.


Assuntos
Procedimentos Cirúrgicos Robóticos , Robótica , Masculino , Humanos , Feminino , Procedimentos Cirúrgicos Robóticos/métodos , Estudos de Viabilidade , Dióxido de Carbono , Prostatectomia , Cateteres Urinários , Carbono , Resultado do Tratamento
14.
J Org Chem ; 88(13): 9157-9166, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37364258

RESUMO

Dynamic covalent chemistry (DCvC) is a powerful means by which to rapidly prepare complex structures from simple molecular building blocks. Effective DCvC behavior is contingent upon the reversibility of covalent bond formation. Stabilized radical species, therefore, have been effectively used for these applications. In earlier work we demonstrated that properly substituted 1-arylurazolyl radicals showed promise as oxygen-insensitive heterocyclic N-centered radicals with a propensity for reversible bond formation. In this work we have synthesized several tethered bis(urazolyl) diradicals, varying by the type and length of connectivity between the urazole rings, and tested them for DCvC behavior. We have found that when the two aryl rings to which the urazolyl radical sites are attached are tethered by a chain of five or more carbons, equilibrium mixtures of monomeric and dimeric species are formed by N-N bond formation between two radical sites. DCvC behavior is observed that is sensitive to changes in temperature, concentration, and (to a lesser extent) solvent. In general, the dimer species is favored at lower temperatures and higher concentrations.

15.
Cell Death Discov ; 9(1): 200, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37386001

RESUMO

Colorectal cancer possesses marked intratumoral heterogeneity. While subclonal interactions between Vogelstein driver mutations have been extensively studied, less is known about competitive or cooperative effects between subclonal populations with other cancer driver mutations. FBXW7 is a cancer driver mutation which is present in close to 17% of colorectal cancer cells. In this study, we generated isogenic FBXW7 mutant cells using CRISPR-Cas9. We identified an upregulation of oxidative phosphorylation and DNA damage in FBXW7 mutant cells, which surprisingly proliferated at a decreased rate compared to wildtype cells. To determine subclonal interactions, wildtype and mutant FBXW7 cells were cocultured using a Transwell system. Wildtype cells cocultured with FBXW7 mutant cells similarly developed DNA damage which was not observed when wildtype cells were co-cultured with other wildtype cells, suggesting that FBXW7 mutant cells were inducing DNA damage in neighbouring wildtype cells. Using mass spectrometry, we identified AKAP8 as being secreted by FBXW7 mutant cells into the coculture media. Furthermore, overexpression of AKAP8 in wildtype cells recapitulated the DNA damage phenotype observed during coculture, while co-culture of wildtype cells with double mutant FBXW7-/-/AKAP8-/- cells abrogated the DNA damage phenotype. Here, we describe a hitherto unknown phenomenon of AKAP8-mediated DNA damage from FBXW7 mutant to neighbouring wildtype cells. Our findings demonstrate the importance of elucidating the local effect of cancer driver mutations between subclonal populations.

16.
Drug Metab Dispos ; 51(7): 873-883, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37308298

RESUMO

Iptacopan (LNP023) is an oral, small-molecule, first-in-class, highly potent proximal complement inhibitor that specifically binds factor B and inhibits the alternative complement pathway. Iptacopan is currently in development as a targeted treatment of paroxysmal nocturnal hemoglobinuria and multiple other complement-mediated diseases. In this study, the absorption, distribution, metabolism, and excretion (ADME) of iptacopan was characterized in six healthy volunteers after a single 100 mg oral dose of [14C]iptacopan. This was supplemented with an in vivo rat ADME study and metabolite exposure comparisons between human, rat, and dog, in addition to in vitro assays, to better understand the clearance pathways and enzymes involved in the metabolism of iptacopan. The fraction of [14C]iptacopan absorbed was estimated to be about 71%, with a time to maximum concentration of 1.5 hours and elimination half-life from plasma of 12.3 hours. Following a single dose of [14C]iptacopan, 71.5% of the radioactivity was recovered in feces and 24.8% in urine. [14C]iptacopan was primarily eliminated by hepatic metabolism. The main biotransformation pathways were oxidative metabolism via CYP2C8, with M2 being the major oxidative metabolite, and acyl glucuronidation via UGT1A1. The two acyl glucuronide metabolites in human plasma, M8 and M9, each accounted for ≤ 10% of the total circulating drug-related material; systemic exposure was also observed in toxicology studies in rat and dog, suggesting a low risk associated with these metabolites. Binding of iptacopan to its target, factor B, in the bloodstream led to a concentration-dependent blood:plasma distribution and plasma protein binding of [14C]iptacopan. SIGNIFICANCE STATEMENT: We characterized the pharmacokinetics, excretion, metabolism and elimination of [14C]iptacopan (an oral, selective small-molecule inhibitor of factor B) in healthy human subjects. [14C]iptacopan was primarily eliminated by metabolism. The primary biotransformation pathways were oxidative metabolism via CYP2C8 and acyl glucuronidation via UGT1A1. Direct secretion of iptacopan into urine and potentially bile represented additional elimination mechanisms. Binding of iptacopan to its target, factor B, in the bloodstream led to a concentration-dependent blood:plasma distribution and plasma protein binding of [14C]iptacopan.


Assuntos
Fator B do Complemento , Humanos , Masculino , Ratos , Animais , Cães , Citocromo P-450 CYP2C8 , Voluntários Saudáveis , Fator B do Complemento/análise , Biotransformação , Fezes/química
17.
J Robot Surg ; 17(5): 2027-2033, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37131055

RESUMO

Robot-assisted radical prostatectomy (RARP) in men with body mass index (BMI) ≥ 35 kg/m2 is considered technically challenging. We conducted a retrospective matched-pair analysis to compare the oncological and functional outcomes of RARP in men with BMI ≥ 35 kg/m2. We interrogated our prospectively maintained RARP database and identified 1273 men who underwent RARP from January 2018 till June 2021. Among them, 43 had BMI ≥ 35 kg/m2, and 1230 had BMI < 35 kg/m2. A 1:1 genetic matching was performed between these two groups for PSA, Gleason grades, clinical stage, D'Amico risk stratification, and nerve-spare extent. Continence rates and biochemical rates on 1-year follow-up were analysed. We performed statistical analysis using SPSS, and Paired tests were done using Wilcoxon sign rank-sum test. p < 0.05 was considered statistically significant. The two groups were comparable in almost all parameters except for age. Console time (p = 0.20) and estimated blood loss (p > 0.90) were not significantly different. There was no blood transfusion, open conversion or (Clavien-Dindo grade ≥ 3) intra/postoperative complication in either of the two groups. The two groups did not have any difference in biochemical recurrence rates (BCR) on 1-year follow-up (p > 0.90). Men with BMI ≥ 35 achieved continence rates equivalent to men with BMI < 35 within 1 year. On logistic regression analysis, age (p < 0.001) and extent of nerve sparing (p = 0.026) emerged as significant factors influencing continence recovery. RARP is safe in men with BMI ≥ 35 kg/m2. The 1-year continence and oncological outcomes are similar to matched men with BMI < 35 kg/m2 undergoing RARP.


Assuntos
Procedimentos Cirúrgicos Robóticos , Robótica , Masculino , Humanos , Procedimentos Cirúrgicos Robóticos/métodos , Análise por Pareamento , Estudos Retrospectivos , Resultado do Tratamento , Prostatectomia , Obesidade/complicações
18.
ACS Appl Mater Interfaces ; 15(19): 22854-22863, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37141163

RESUMO

Biocompatible and plastic neural interface devices allow for minimally invasive recording of brain activity. Increasing electrode density in such devices is essential for high-resolution neural recordings. Superimposing conductive leads in devices can help multiply the number of recording sites while keeping probes width small and suitable for implantation. However, because of leads' vertical proximity, this can create capacitive coupling (CC) between overlapping channels, which leads to crosstalk. Here, we present a thorough investigation of CC phenomenon in multi-gold layer thin-film multi-electrode arrays with a parylene C (PaC) insulation layer between superimposed leads. We also propose a guideline on the design, fabrication, and characterization of such type of neural interface devices for high spatial resolution recording. Our results demonstrate that the capacitance created through CC between superimposed tracks decreases non-linearly and then linearly with the increase of insulation thickness. We identify an optimal PaC insulation thickness that leads to a drastic reduction of CC between superimposed gold channels while not significantly increasing the overall device thickness. Finally, we show that double gold layer electrocorticography probes with the optimal insulation thickness exhibit similar performances in vivo when compared to single-layer devices. This confirms that these probes are adequate for high-quality neural recordings.


Assuntos
Eletrocorticografia , Ouro , Eletrodos , Condutividade Elétrica , Capacitância Elétrica , Eletrodos Implantados , Microeletrodos
19.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1536523

RESUMO

(analítico) Se presentan los resultados de una investigación de corte cualitativo que, a través de historias de vida, tuvo como propósito conocer las experiencias de mujeres jóvenes vinculadas a pandillas salvadoreñas. Las jóvenes participantes fueron seleccionadas de un proyecto sociocultural conocido como la Orquesta de Cuerdas del Centro para la Inserción Social. A partir de entrevistas a profundidad y un trabajo de relato autobiográfico, las jóvenes reconstruyeron sus historias permitiendo identificar cuatro resultados relevantes: los contextos de violencia en los cuales viven sus infancias, las motivaciones y significados de la pandilla para las jóvenes, la violencia y los roles de género que experimentan continuamente y el encuentro con el arte como una práctica de re-existencia que les permite resignificar su vida.


(analytical) This article describes the results of qualitative research focused on the life stories of a group of young women with the objective of learning about their experiences as members of Salvadoran gangs. The participants were selected from a sociocultural project known as the Center for Social Insertion String Orchestra. The young women created their life stories through in-depth interviews and autobiographical narrative work, which facilitated the identification of four relevant results: the contexts of violence that defined their childhood; the motivations and meanings of gang membership for young women; the violence and gender roles they experience; and their artistic practice as a re-existence that allows them to resignify their lives.


(analítico) Este artigo contém os resultados de uma pesquisa qualitativa através das histórias de vida desse grupo de mulheres jovens com o objetivo de conhecer suas experiências ligadas às gangues salvadorenhas. As jovens participantes foram selecionadas a partir de um projeto sociocultural conhecido como Centro de Inserção Social Orquestra de Cordas. A partir de entrevistas em profundidade e trabalho de narrativa autobiográfica, as jovens reconstruíram suas histórias, permitindo a identificação de quatro resultados relevantes: os contextos de violência em que vivem suas infâncias, as motivações e significados da gangue para as jovens, a violência e os papéis de gênero que vivenciam como um continuum e o encontro com a arte como prática de re-existência que lhes permite ressignificar suas vidas.

20.
Curr Biol ; 33(8): 1431-1447.e22, 2023 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-36958333

RESUMO

Ludwig van Beethoven (1770-1827) remains among the most influential and popular classical music composers. Health problems significantly impacted his career as a composer and pianist, including progressive hearing loss, recurring gastrointestinal complaints, and liver disease. In 1802, Beethoven requested that following his death, his disease be described and made public. Medical biographers have since proposed numerous hypotheses, including many substantially heritable conditions. Here we attempt a genomic analysis of Beethoven in order to elucidate potential underlying genetic and infectious causes of his illnesses. We incorporated improvements in ancient DNA methods into existing protocols for ancient hair samples, enabling the sequencing of high-coverage genomes from small quantities of historical hair. We analyzed eight independently sourced locks of hair attributed to Beethoven, five of which originated from a single European male. We deemed these matching samples to be almost certainly authentic and sequenced Beethoven's genome to 24-fold genomic coverage. Although we could not identify a genetic explanation for Beethoven's hearing disorder or gastrointestinal problems, we found that Beethoven had a genetic predisposition for liver disease. Metagenomic analyses revealed furthermore that Beethoven had a hepatitis B infection during at least the months prior to his death. Together with the genetic predisposition and his broadly accepted alcohol consumption, these present plausible explanations for Beethoven's severe liver disease, which culminated in his death. Unexpectedly, an analysis of Y chromosomes sequenced from five living members of the Van Beethoven patrilineage revealed the occurrence of an extra-pair paternity event in Ludwig van Beethoven's patrilineal ancestry.


Assuntos
Surdez , Pessoas Famosas , Música , Masculino , Humanos , Predisposição Genética para Doença , Genômica , Cabelo
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