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1.
J Med Chem ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39013156

RESUMO

Fibroblast activation protein (FAP) has attracted considerable attention as a possible target for the radiotherapy of solid tumors. Unfortunately, initial efforts to treat solid tumors with FAP-targeted radionuclides have yielded only modest clinical responses, suggesting that further improvements in the molecular design of FAP-targeted radiopharmaceutical therapies (RPT) are warranted. In this study, we report several advances on the previously described FAP6 radioligand that increase tumor retention and accelerate healthy tissue clearance. Seven FAP6 derivatives with different linkers or albumin binders were synthesized, radiolabeled, and investigated for their effects on binding and cellular uptake. The radioligands were then characterized in 4T1 tumor-bearing Balb/c mice using both single-photon emission computed tomography (SPECT) and ex vivo biodistribution analyses to identify the conjugate with the best tumor retention and tumor-to-healthy organ ratios. The results reveal an optimized FAP6 radioligand that exhibits efficacy and safety properties that potentially justify its translation into the clinic.

2.
J Nucl Med ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38871387

RESUMO

Because of upregulated expression on cancer-associated fibroblasts, fibroblast activation protein (FAP) has emerged as an attractive biomarker for the imaging and therapy of solid tumors. Although many FAP ligands have already been developed for radiopharmaceutical therapies (RPTs), most suffer from inadequate tumor uptake, insufficient tumor residence times, or off-target accumulation in healthy tissues, suggesting a need for further improvements. Methods: A new FAP-targeted RPT with a novel ligand (FAP8-PEG3-IP-DOTA) was designed by combining the desirable features of several previous ligand-targeted RPTs. Uptake and retention of [111In]In or [177Lu]Lu-FAP8-PEG3-IP-DOTA were assessed in KB, HT29, MDA-MB-231, and 4T1 murine tumor models by radioimaging or ex vivo biodistribution analyses. Radiotherapeutic potencies and gross toxicities were also investigated by monitoring tumor growth, body weight, and tissue damage in tumor-bearing mice. Results: FAP8-PEG3-IP-DOTA exhibited high affinity (half-maximal inhibitory concentration, 1.6 nM) and good selectivity for FAP relative to its closest homologs, prolyl oligopeptidase (half-maximal inhibitory concentration, ∼14.0 nM) and dipeptidyl peptidase-IV (half-maximal inhibitory concentration, ∼860 nM). SPECT/CT scans exhibited high retention in 2 different solid tumor models and minimal uptake in healthy tissues. Quantitative biodistribution analyses revealed tumor-to-healthy-tissue ratios of more than 5 times for all major organs, and live animal studies demonstrated 65%-93% suppression of tumor growth in all 4 models tested, with minimal or no evidence of systemic toxicity. Conclusion: We conclude that [177Lu]Lu-FAP8-PEG3-IP-DOTA constitutes a promising and safe RPT candidate for FAPα-targeted radionuclide therapy of solid tumors.

3.
Am J Cardiol ; 203: 429-435, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37536045

RESUMO

Continuous exposure to low-level scattered radiation to staff performing cardiac angiography and intervention is of concern. A novel shielding solution (NSS) (Rampart IC M1128) has the potential to provide greater shielding for staff present at the table-side. This study aimed to investigate the effectiveness of the NSS compared with a traditional shielding solution (TSS) in a randomized controlled trial that enrolled 100 patients who underwent cardiac angiography and/or intervention which were randomized to the NSS or TSS. Baseline patient characteristics and radiation dose data were collected. Staff who were scrubbed at the table-side wore 5 real-time dosimeters on the head, collar, waist, ankle, and under the apron. The median primary operator radiation dose was significantly lower (p <0.001) for all dosimeter locations with the NSS when compared with the TSS, being reduced by 86%, 80.0%, 100%, and 50.0% for the head, collar, waist, and leg respectively. Median under-apron dose was 0.0 µSv for both NSS and TSS. Median second operator dose was reduced by 100%, 100%, and 100% for the head, collar, and waist respectively (p <0.001). Median NSS and TSS dose at the ankle and under apron was 0.0 µSv. Median scrub nurse dose was reduced by 50% and 100% for the head and collar respectively (p <0.001). Median NSS and TSS dose at the waist, ankle, and under apron was 0.0 µSv. In conclusion, the NSS tested in this study demonstrates a significant decrease in radiation dose to operators and scrub nurses when compared with traditional radiation protection measures.


Assuntos
Exposição Ocupacional , Exposição à Radiação , Proteção Radiológica , Humanos , Cateteres Cardíacos , Exposição Ocupacional/prevenção & controle , Doses de Radiação , Exposição à Radiação/prevenção & controle
4.
J Extracell Vesicles ; 12(7): e12332, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37353884

RESUMO

The release of growth factors, cytokines and extracellular matrix modifiers by activated platelets is an important step in the process of healthy wound healing. Extracellular vesicles (EVs) released by activated platelets carry this bioactive cargo in an enriched form, and may therefore represent a potential therapeutic for the treatment of delayed wound healing, such as chronic wounds. While EVs show great promise in regenerative medicine, their production at clinical scale remains a critical challenge and their tolerability in humans is still to be fully established. In this work, we demonstrate that Ligand-based Exosome Affinity Purification (LEAP) chromatography can successfully isolate platelet EVs (pEVs) of clinical grade from activated platelets, which retain the regenerative properties of the parent cell. LEAP-isolated pEVs display the expected biophysical features of EV populations and transport essential proteins in wound healing processes, including insulin growth factor (IGF) and transforming growth factor beta (TGF-ß). In vitro studies show that pEVs induce proliferation and migration of dermal fibroblasts and increase dermal endothelial cells' angiogenic potential, demonstrating their wound healing potential. pEV treatment activates the ERK and Akt signalling pathways within recipient cells. In a first-in-human, double-blind, placebo-controlled, phase I clinical trial of healthy volunteer adults, designed primarily to assess safety in the context of wound healing, we demonstrate that injections of LEAP-purified pEVs in formulation buffer are safe and well tolerated (Plexoval II study, ACTRN12620000944932). As a secondary objective, biological activity in the context of wound healing rate was assessed. In this cohort of healthy participants, in which the wound bed would not be expected to be deficient in the bioactive cargo that pEVs carry, all wounds healed rapidly and completely and no difference in time to wound closure of the treated and untreated wounds was observed at the single dose tested. The outcomes of this study evidence that pEVs manufactured through the LEAP process can be injected safely in humans as a potential wound healing treatment, and warrant further study in clinical trials designed expressly to assess therapeutic efficacy in patients with delayed or disrupted wound healing.


Assuntos
Vesículas Extracelulares , Transplante de Células-Tronco Hematopoéticas , Adulto , Humanos , Plaquetas/metabolismo , Células Endoteliais , Vesículas Extracelulares/metabolismo , Cicatrização/fisiologia
5.
Nat Chem ; 15(7): 998-1005, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37217786

RESUMO

γ-Amino acids can play important roles in the biological activities of natural products; however, the ribosomal incorporation of γ-amino acids into peptides is challenging. Here we report how a selection campaign employing a non-canonical peptide library containing cyclic γ2,4-amino acids resulted in the discovery of very potent inhibitors of the SARS-CoV-2 main protease (Mpro). Two kinds of cyclic γ2,4-amino acids, cis-3-aminocyclobutane carboxylic acid (γ1) and (1R,3S)-3-aminocyclopentane carboxylic acid (γ2), were ribosomally introduced into a library of thioether-macrocyclic peptides. One resultant potent Mpro inhibitor (half-maximal inhibitory concentration = 50 nM), GM4, comprising 13 residues with γ1 at the fourth position, manifests a 5.2 nM dissociation constant. An Mpro:GM4 complex crystal structure reveals the intact inhibitor spans the substrate binding cleft. The γ1 interacts with the S1' catalytic subsite and contributes to a 12-fold increase in proteolytic stability compared to its alanine-substituted variant. Knowledge of interactions between GM4 and Mpro enabled production of a variant with a 5-fold increase in potency.


Assuntos
Aminoácidos , COVID-19 , Aminoácidos/química , Antivirais/química , Ácidos Carboxílicos , Peptídeos/química , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Conformação Proteica , SARS-CoV-2/metabolismo
6.
J Nucl Med ; 64(5): 759-766, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37116911

RESUMO

Fibroblast activation protein (FAP) has received increasing attention as an oncologic target because of its prominent expression in solid tumors but virtual absence from healthy tissues. Most radioligand therapies (RLTs) targeting FAP, however, suffer from inadequate tumor retention or clearance from healthy tissues. Herein we report a FAP-targeted RLT comprising an FAP6 ligand conjugated to DOTA and an albumin binder (4-p-iodophenylbutyric acid, or IP) for enhanced pharmacokinetics. We evaluated the performance of the resulting FAP6-IP-DOTA conjugate in 4 tumor models, 3 of which express FAP only on cancer-associated fibroblasts, that is, analogously to human tumors. Methods: Single-cell RNA-sequencing data were analyzed from 34 human breast, ovarian, colorectal, and lung cancers to quantify FAP-overexpressing cells. FAP6-DOTA conjugates were synthesized with or without an albumin binder (IP) and investigated for binding to human FAP-expressing cells. Accumulation of 111In- or 177Lu-labeled conjugates in KB, HT29, U87MG, and 4T1 murine tumors was also assessed by radioimaging or biodistribution analyses. Radiotherapeutic potency was quantitated by measuring tumor volumes versus time. Results: Approximately 5% of all cells in human tumors overexpressed FAP (cancer-associated fibroblasts comprised ∼77% of this FAP-positive subpopulation, whereas ∼2% were cancer cells). FAP6 conjugates bound to FAP-expressing cells with high affinity (dissociation constant, ∼1 nM). 177Lu-FAP6-IP-DOTA achieved an 88-fold higher tumor dose than 177Lu-FAP6-DOTA and improved all tumor-to-healthy-organ ratios. Single doses of 177Lu-FAP6-IP-DOTA suppressed tumor growth by about 45% in all tested tumor models without causing reproducible toxicities. Conclusion: We conclude that 177Lu-FAP6-IP-DOTA constitutes a promising candidate for FAP-targeted RLT of solid tumors.


Assuntos
Albuminas , Fibroblastos , Humanos , Animais , Camundongos , Distribuição Tecidual , Linhagem Celular Tumoral
7.
J Chem Inf Model ; 63(9): 2866-2880, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-37058135

RESUMO

SARS-CoV-2 is the causative agent of COVID-19 and is responsible for the current global pandemic. The viral genome contains 5 major open reading frames of which the largest ORF1ab codes for two polyproteins, pp1ab and pp1a, which are subsequently cleaved into 16 nonstructural proteins (nsp) by two viral cysteine proteases encoded within the polyproteins. The main protease (Mpro, nsp5) cleaves the majority of the nsp's, making it essential for viral replication and has been successfully targeted for the development of antivirals. The first oral Mpro inhibitor, nirmatrelvir, was approved for treatment of COVID-19 in late December 2021 in combination with ritonavir as Paxlovid. Increasing the arsenal of antivirals and development of protease inhibitors and other antivirals with a varied mode of action remains a priority to reduce the likelihood for resistance emerging. Here, we report results from an artificial intelligence-driven approach followed by in vitro validation, allowing the identification of five fragment-like Mpro inhibitors with IC50 values ranging from 1.5 to 241 µM. The three most potent molecules (compounds 818, 737, and 183) were tested against SARS-CoV-2 by in vitro replication in Vero E6 and Calu-3 cells. Compound 818 was active in both cell models with an EC50 value comparable to its measured IC50 value. On the other hand, compounds 737 and 183 were only active in Calu-3, a preclinical model of respiratory cells, showing selective indexes twice as high as those for compound 818. We also show that our in silico methodology was successful in identifying both reversible and covalent inhibitors. For instance, compound 818 is a reversible chloromethylamide analogue of 8-methyl-γ-carboline, while compound 737 is an N-pyridyl-isatin that covalently inhibits Mpro. Given the small molecular weights of these fragments, their high binding efficiency in vitro and efficacy in blocking viral replication, these compounds represent good starting points for the development of potent lead molecules targeting the Mpro of SARS-CoV-2.


Assuntos
Antivirais , COVID-19 , Humanos , Antivirais/farmacologia , Antivirais/química , SARS-CoV-2 , Inteligência Artificial , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química , Simulação de Acoplamento Molecular
8.
Nat Commun ; 14(1): 1545, 2023 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-36941262

RESUMO

The main protease from SARS-CoV-2 (Mpro) is responsible for cleavage of the viral polyprotein. Mpro self-processing is called maturation, and it is crucial for enzyme dimerization and activity. Here we use C145S Mpro to study the structure and dynamics of N-terminal cleavage in solution. Native mass spectroscopy analysis shows that mixed oligomeric states are composed of cleaved and uncleaved particles, indicating that N-terminal processing is not critical for dimerization. A 3.5 Å cryo-EM structure provides details of Mpro N-terminal cleavage outside the constrains of crystal environment. We show that different classes of inhibitors shift the balance between oligomeric states. While non-covalent inhibitor MAT-POS-e194df51-1 prevents dimerization, the covalent inhibitor nirmatrelvir induces the conversion of monomers into dimers, even with intact N-termini. Our data indicates that the Mpro dimerization is triggered by induced fit due to covalent linkage during substrate processing rather than the N-terminal processing.


Assuntos
Proteases 3C de Coronavírus , SARS-CoV-2 , Antivirais , Inibidores de Proteases/farmacologia , SARS-CoV-2/enzimologia , Proteases 3C de Coronavírus/química
9.
J Med Chem ; 66(4): 2663-2680, 2023 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-36757959

RESUMO

Nirmatrelvir (PF-07321332) is a nitrile-bearing small-molecule inhibitor that, in combination with ritonavir, is used to treat infections by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Nirmatrelvir interrupts the viral life cycle by inhibiting the SARS-CoV-2 main protease (Mpro), which is essential for processing viral polyproteins into functional nonstructural proteins. We report studies which reveal that derivatives of nirmatrelvir and other Mpro inhibitors with a nonactivated terminal alkyne group positioned similarly to the electrophilic nitrile of nirmatrelvir can efficiently inhibit isolated Mpro and SARS-CoV-2 replication in cells. Mass spectrometric and crystallographic evidence shows that the alkyne derivatives inhibit Mpro by apparent irreversible covalent reactions with the active site cysteine (Cys145), while the analogous nitriles react reversibly. The results highlight the potential for irreversible covalent inhibition of Mpro and other nucleophilic cysteine proteases by alkynes, which, in contrast to nitriles, can be functionalized at their terminal position to optimize inhibition and selectivity, as well as pharmacodynamic and pharmacokinetic properties.


Assuntos
Antivirais , COVID-19 , Proteases 3C de Coronavírus , Nitrilas , SARS-CoV-2 , Inibidores de Protease Viral , Humanos , Antivirais/farmacologia , Cisteína/química , SARS-CoV-2/metabolismo , Proteínas não Estruturais Virais/metabolismo , Inibidores de Protease Viral/farmacologia
10.
J Med Chem ; 65(11): 7682-7696, 2022 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-35549342

RESUMO

The SARS-CoV-2 main protease (Mpro) is a medicinal chemistry target for COVID-19 treatment. Given the clinical efficacy of ß-lactams as inhibitors of bacterial nucleophilic enzymes, they are of interest as inhibitors of viral nucleophilic serine and cysteine proteases. We describe the synthesis of penicillin derivatives which are potent Mpro inhibitors and investigate their mechanism of inhibition using mass spectrometric and crystallographic analyses. The results suggest that ß-lactams have considerable potential as Mpro inhibitors via a mechanism involving reaction with the nucleophilic cysteine to form a stable acyl-enzyme complex as shown by crystallographic analysis. The results highlight the potential for inhibition of viral proteases employing nucleophilic catalysis by ß-lactams and related acylating agents.


Assuntos
Tratamento Farmacológico da COVID-19 , Cisteína , Antivirais/química , Antivirais/farmacologia , Proteases 3C de Coronavírus , Cisteína Endopeptidases/química , Humanos , Penicilinas , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , SARS-CoV-2 , beta-Lactamas
11.
Br J Neurosurg ; 36(2): 175-178, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33302746

RESUMO

INTRODUCTION: Internal neurolysis (INL) is a surgical procedure where trigeminal nerve fibres are separated between the pons and porus trigeminus to relieve trigeminal neuralgia (TN). We report pain and functional outcomes to evaluate its safety and efficacy. MATERIALS AND METHODS: Prospective cohort of all patients undergoing retrosigmoid craniotomy and INL between 2015 and 2017 at University Hospital Southampton. Patients with type I (6) or type II (2) refractory TN and no clear neurovascular conflict were offered INL as an alternative to partial sensory rhizotomy. Barrow Pain Intensity Scale (BNI) and Brief Pain Inventory Facial scores (BPI-Facial) were assessed. Minimum follow-up was 2 years'. RESULTS: Eight patients (7F:1M) underwent INL. Two had MS. Pre-operatively, all had severe pain (BNI grade V) and the median BPI-Facial score was 115 (range 79-123).. There were no unexpected complications. On last follow-up, six (75%) had no pain (BNI grade I), while two (25%) had recurred (at 5 and 27 months). Median BPI-Facial score for all patients on the last follow-up was 20 (range 18-91) reflecting dramatically improved quality of life and activities. CONCLUSIONS: INL is a potentially safe and effective treatment for refractory TN. Long-term efficacy is unknown, but early results are promising.


Assuntos
Radiocirurgia , Neuralgia do Trigêmeo , Humanos , Dor/cirurgia , Estudos Prospectivos , Qualidade de Vida , Radiocirurgia/métodos , Estudos Retrospectivos , Resultado do Tratamento , Nervo Trigêmeo/cirurgia , Neuralgia do Trigêmeo/cirurgia , Reino Unido
12.
Cell Chem Biol ; 28(12): 1795-1806.e5, 2021 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-34174194

RESUMO

Designing covalent inhibitors is increasingly important, although it remains challenging. Here, we present covalentizer, a computational pipeline for identifying irreversible inhibitors based on structures of targets with non-covalent binders. Through covalent docking of tailored focused libraries, we identify candidates that can bind covalently to a nearby cysteine while preserving the interactions of the original molecule. We found âˆ¼11,000 cysteines proximal to a ligand across 8,386 complexes in the PDB. Of these, the protocol identified 1,553 structures with covalent predictions. In a prospective evaluation, five out of nine predicted covalent kinase inhibitors showed half-maximal inhibitory concentration (IC50) values between 155 nM and 4.5 µM. Application against an existing SARS-CoV Mpro reversible inhibitor led to an acrylamide inhibitor series with low micromolar IC50 values against SARS-CoV-2 Mpro. The docking was validated by 12 co-crystal structures. Together these examples hint at the vast number of covalent inhibitors accessible through our protocol.


Assuntos
Desenho de Fármacos , Inibidores de Proteínas Quinases/química , SARS-CoV-2/enzimologia , Proteínas da Matriz Viral/antagonistas & inibidores , Acrilamida/química , Acrilamida/metabolismo , Sítios de Ligação , COVID-19/patologia , COVID-19/virologia , Domínio Catalítico , Biologia Computacional/métodos , Bases de Dados de Proteínas , Humanos , Concentração Inibidora 50 , Simulação de Acoplamento Molecular , Inibidores de Proteínas Quinases/metabolismo , SARS-CoV-2/isolamento & purificação , Proteínas da Matriz Viral/metabolismo
13.
Ann Oncol ; 32(7): 917-925, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33798657

RESUMO

BACKGROUND: Immune-related adverse events (irAEs) typically occur within 4 months of starting anti-programmed cell death protein 1 (PD-1)-based therapy [anti-PD-1 ± anti-cytotoxic T-lymphocyte-associated protein 4 (CTLA4)], but delayed irAEs (onset >12 months after commencement) can also occur. This study describes the incidence, nature and management of delayed irAEs in patients receiving anti-PD-1-based immunotherapy. PATIENTS AND METHODS: Patients with delayed irAEs from 20 centres were studied. The incidence of delayed irAEs was estimated as a proportion of melanoma patients treated with anti-PD-1-based therapy and surviving >1 year. Onset, clinical features, management and outcomes of irAEs were examined. RESULTS: One hundred and eighteen patients developed a total of 140 delayed irAEs (20 after initial combination with anti-CTLA4), with an estimated incidence of 5.3% (95% confidence interval 4.0-6.9, 53/999 patients at sites with available data). The median onset of delayed irAE was 16 months (range 12-53 months). Eighty-seven patients (74%) were on anti-PD-1 at irAE onset, 15 patients (12%) were <3 months from the last dose and 16 patients (14%) were >3 months from the last dose of anti-PD-1. The most common delayed irAEs were colitis, rash and pneumonitis; 55 of all irAEs (39%) were ≥grade 3. Steroids were required in 80 patients (68%), as well as an additional immunosuppressive agent in 27 patients (23%). There were two irAE-related deaths: encephalitis with onset during anti-PD-1 and a multiple-organ irAE with onset 11 months after ceasing anti-PD-1. Early irAEs (<12 months) had also occurred in 69 patients (58%), affecting a different organ from the delayed irAE in 59 patients (86%). CONCLUSIONS: Delayed irAEs occur in a small but relevant subset of patients. Delayed irAEs are often different from previous irAEs, may be high grade and can lead to death. They mostly occur in patients still receiving anti-PD-1. The risk of delayed irAE should be considered when deciding the duration of treatment in responding patients. However, patients who stop treatment may also rarely develop delayed irAE.


Assuntos
Melanoma , Pneumonia , Humanos , Fatores Imunológicos , Imunoterapia/efeitos adversos , Melanoma/tratamento farmacológico , Estudos Retrospectivos
14.
Chem Commun (Camb) ; 57(12): 1430-1433, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33462575

RESUMO

The main viral protease (Mpro) of SARS-CoV-2 is a nucleophilic cysteine hydrolase and a current target for anti-viral chemotherapy. We describe a high-throughput solid phase extraction coupled to mass spectrometry Mpro assay. The results reveal some ß-lactams, including penicillin esters, are active site reacting Mpro inhibitors, thus highlighting the potential of acylating agents for Mpro inhibition.


Assuntos
Antivirais/farmacologia , Cisteína Endopeptidases/efeitos dos fármacos , Espectrometria de Massas/métodos , Inibidores de Proteases/farmacologia , SARS-CoV-2/efeitos dos fármacos , beta-Lactamas/farmacologia , Acilação , Antivirais/química , COVID-19/virologia , Domínio Catalítico , Ensaios de Triagem em Larga Escala , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Inibidores de Proteases/química , SARS-CoV-2/enzimologia , beta-Lactamas/química
15.
Br J Neurosurg ; 35(4): 462-466, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33513028

RESUMO

INTRODUCTION: Intracranial arachnoid cysts are a common incidental finding; however presentation with cyst rupture is a recognised complication. Patients are advised to avoid contact sports to reduce the risk of cyst rupture but the risk of rupture is not currently known. The aim of this study is to describe a single institution's experience of managing ruptured intra-cranial arachnoid cysts. METHOD: A retrospective case note review of all patients admitted to a single institution with a ruptured intra-cranial arachnoid cyst between 2005 and 2016 (inclusive). Medical records were reviewed for demographics, history of trauma, surgical treatment and radiological evidence of cyst rupture. RESULTS: Fourteen patients were identified for inclusion with an average age of 23.4 years (range 7-57) and 10 (71%) were male. Nine patients (64%) had a documented history of head trauma. Eleven patients (78.6%) required neurosurgical intervention which included hygroma/haematoma evacuation only (n = 5), haematoma evacuation with cyst fenestration (n = 4) and cyst fenestration/shunting only (n = 2). Twelve patients (85%) experienced full recovery and the remaining two had persisting headaches or neurological symptoms. DISCUSSION: Cyst rupture remains an uncommon cause for presentation with arachnoid cysts. However the majority are associated with head trauma and thus current advice to avoid contact sports seems justified.


Assuntos
Cistos Aracnóideos , Adolescente , Adulto , Cistos Aracnóideos/complicações , Cistos Aracnóideos/diagnóstico por imagem , Cistos Aracnóideos/cirurgia , Criança , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos , Estudos Retrospectivos , Ruptura , Reino Unido , Adulto Jovem
16.
Cell Mol Life Sci ; 78(2): 675-693, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32333083

RESUMO

The availability and repartition of fucosylated glycans within the gastrointestinal tract contributes to the adaptation of gut bacteria species to ecological niches. To access this source of nutrients, gut bacteria encode α-L-fucosidases (fucosidases) which catalyze the hydrolysis of terminal α-L-fucosidic linkages. We determined the substrate and linkage specificities of fucosidases from the human gut symbiont Ruminococcus gnavus. Sequence similarity network identified strain-specific fucosidases in R. gnavus ATCC 29149 and E1 strains that were further validated enzymatically against a range of defined oligosaccharides and glycoconjugates. Using a combination of glycan microarrays, mass spectrometry, isothermal titration calorimetry, crystallographic and saturation transfer difference NMR approaches, we identified a fucosidase with the capacity to recognize sialic acid-terminated fucosylated glycans (sialyl Lewis X/A epitopes) and hydrolyze α1-3/4 fucosyl linkages in these substrates without the need to remove sialic acid. Molecular dynamics simulation and docking showed that 3'-Sialyl Lewis X (sLeX) could be accommodated within the binding site of the enzyme. This specificity may contribute to the adaptation of R. gnavus strains to the infant and adult gut and has potential applications in diagnostic glycomic assays for diabetes and certain cancers.


Assuntos
Proteínas de Bactérias/metabolismo , Clostridiales/metabolismo , Microbioma Gastrointestinal , alfa-L-Fucosidase/metabolismo , Proteínas de Bactérias/química , Clostridiales/química , Clostridiales/enzimologia , Trato Gastrointestinal/microbiologia , Glicoconjugados/metabolismo , Humanos , Oligossacarídeos/metabolismo , Polissacarídeos/metabolismo , Especificidade por Substrato , alfa-L-Fucosidase/química
17.
Nat Commun ; 11(1): 5047, 2020 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-33028810

RESUMO

COVID-19, caused by SARS-CoV-2, lacks effective therapeutics. Additionally, no antiviral drugs or vaccines were developed against the closely related coronavirus, SARS-CoV-1 or MERS-CoV, despite previous zoonotic outbreaks. To identify starting points for such therapeutics, we performed a large-scale screen of electrophile and non-covalent fragments through a combined mass spectrometry and X-ray approach against the SARS-CoV-2 main protease, one of two cysteine viral proteases essential for viral replication. Our crystallographic screen identified 71 hits that span the entire active site, as well as 3 hits at the dimer interface. These structures reveal routes to rapidly develop more potent inhibitors through merging of covalent and non-covalent fragment hits; one series of low-reactivity, tractable covalent fragments were progressed to discover improved binders. These combined hits offer unprecedented structural and reactivity information for on-going structure-based drug design against SARS-CoV-2 main protease.


Assuntos
Betacoronavirus/química , Cisteína Endopeptidases/química , Fragmentos de Peptídeos/química , Proteínas não Estruturais Virais/química , Betacoronavirus/enzimologia , Sítios de Ligação , Domínio Catalítico , Proteases 3C de Coronavírus , Cristalografia por Raios X , Cisteína Endopeptidases/metabolismo , Desenho de Fármacos , Espectrometria de Massas , Modelos Moleculares , Fragmentos de Peptídeos/metabolismo , Conformação Proteica , SARS-CoV-2 , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/metabolismo , Eletricidade Estática , Proteínas não Estruturais Virais/metabolismo
18.
Br J Dermatol ; 183(4): 638-649, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32562551

RESUMO

BACKGROUND: The rapid expansion of psoriasis biologics has led to an urgent need to understand their relative efficacy and tolerability to inform treatment decisions better and, specifically, to inform guideline development. OBJECTIVES: To update a 2017 meta-analysis on the comparative efficacy and tolerability of biologic treatments for psoriasis. METHODS: We searched the MEDLINE, PubMed, Embase and Cochrane databases for randomized controlled trials (RCTs), published up to 7 September 2018, of 11 licensed, NICE-approved biologics targeting tumour necrosis factor (adalimumab, etanercept, infliximab, certolizumab pegol), interleukin (IL)-12/IL-23p40 (ustekinumab), IL-17A (secukinumab, ixekizumab), IL-17RA (brodalumab) and IL-23p19 (guselkumab, tildrakizumab, risankizumab). A frequentist network meta-analysis ascertained direct or indirect evidence comparing biologics with one another, methotrexate or placebo. This was combined with hierarchical cluster analyses to consider efficacy (≥ 90% improvement in Psoriasis Area and Severity Index (PASI 90) or Physician's Global Assessment 0 or 1; PASI 75; Dermatology Life Quality Index improvement) and tolerability (drug withdrawal due to adverse events) outcomes at 10-16 weeks, followed by assessments of study quality, heterogeneity and inconsistency. RESULTS: We identified 62 RCTs presenting data on direct comparisons (31 899 participants). All biologics were efficacious compared with placebo or methotrexate at 10-16 weeks. Hierarchical cluster analyses revealed that adalimumab, brodalumab, certolizumab pegol, guselkumab, risankizumab, secukinumab, tildrakizumab and ustekinumab were comparable with respect to high short-term efficacy and tolerability. Infliximab and ixekizumab clustered together, with high short-term efficacy but relatively lower tolerability than the other agents, although the number of drug withdrawal events across the network was low, so these findings should be treated with caution. CONCLUSIONS: Using our methodology we found that most biologics cluster together with respect to short-term efficacy and tolerability, and we did not identify any single agent as 'best'. These data need to be interpreted in the context of longer-term efficacy, effectiveness data, safety, posology and drug acquisition costs when making treatment decisions.


Assuntos
Interleucina-12 , Psoríase , Terapia Biológica , Humanos , Metanálise em Rede , Psoríase/tratamento farmacológico , Ustekinumab
19.
Ann Oncol ; 31(8): 1075-1082, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32387454

RESUMO

BACKGROUND: Anti-programmed cell death protein 1 (PD-1) antibodies (PD1) prolong recurrence-free survival in high-risk resected melanoma; however, approximately 25%-30% of patients recur within 1 year. This study describes the pattern of recurrence, management and outcomes of patients who recur with adjuvant PD1 therapy. PATIENTS AND METHODS: Consecutive patients from 16 centres who recurred having received adjuvant PD1 therapy for resected stage III/IV melanoma were studied. Recurrence characteristics, management and outcomes were examined; patients with mucosal melanoma were analysed separately. RESULTS: Melanoma recurrence occurred in 147 (17%) of ∼850 patients treated with adjuvant PD1. In those with cutaneous melanoma (n = 136), median time to recurrence was 4.6 months (range 0.3-35.7); 104 (76%) recurred during (ON) adjuvant PD1 after a median 3.2 months and 32 (24%) following (OFF) treatment cessation after a median 12.5 months, including in 21 (15%) who ceased early for toxicity. Fifty-nine (43%) recurred with locoregional disease only and 77 (57%) with distant disease. Of those who recurred locally, 22/59 (37%) subsequently recurred distantly. Eighty-nine (65%) patients received systemic therapy after recurrence. Of those who recurred ON adjuvant PD1, none (0/6) responded to PD1 alone; 8/33 assessable patients (24%) responded to ipilimumab (alone or in combination with PD1) and 18/23 (78%) responded to BRAF/MEK inhibitors. Of those who recurred OFF adjuvant PD1, two out of five (40%) responded to PD1 monotherapy, two out of five (40%) responded to ipilimumab-based therapy and 9/10 (90%) responded to BRAF/MEK inhibitors. CONCLUSIONS: Most patients who recur early despite adjuvant PD1 develop distant metastases. In those who recur ON adjuvant PD1, there is minimal activity of further PD1 monotherapy, but ipilimumab (alone or in combination with PD1) and BRAF/MEK inhibitors have clinical utility. Retreatment with PD1 may have activity in select patients who recur OFF PD1.


Assuntos
Melanoma , Neoplasias Cutâneas , Terapia Combinada , Humanos , Imunoterapia , Ipilimumab/uso terapêutico , Melanoma/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico
20.
Clin Transl Oncol ; 22(11): 2002-2008, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32240504

RESUMO

PURPOSE: To describe the oncologic and obstetric outcomes of patients diagnosed with invasive cervical cancer (ICC) and in situ adenocarcinoma (ISA) during pregnancy or during the year following delivery. METHODS: This retrospective observational study involved a cohort of 28 patients diagnosed with invasive cervical cancer (20 patients) or in situ adenocarcinoma (eight patients) during pregnancy or during the year following delivery who received expert opinion from physicians of the Cancer Associé à La Grossesse (CALG) network between 2005 and 2018. Descriptive results were expressed in median, range and interquartile range (IQR). RESULTS: Between 2005 and 2018, 20 patients with ICC and eight with ISA received expert opinion from physicians of the CALG network. Both ICC and ISA were mostly diagnosed during pregnancy with a median term at diagnosis of 23.3 weeks of gestation (WG) for ICC and 7.3 WG for ISA. Overall, the median age at diagnosis for both ICC and ISA was 33 years. Most ICCs (n = 9) had FIGO stage ≥ IB2 and five underwent neoadjuvant chemotherapy at a median term of 22.5 WG. Seventeen patients with ICC underwent surgery. Three patients had medical termination of the pregnancy. Two patients experienced recurrence and three died. Median time of follow-up was 59.3 months (IQR 30.5-129.2). CONCLUSION: Management of cervical cancer during pregnancy is challenging especially in terms of maternal outcomes with a relative poor prognosis requiring a multidisciplinary expert advice.


Assuntos
Adenocarcinoma in Situ/terapia , Complicações Neoplásicas na Gravidez/terapia , Neoplasias do Colo do Útero/terapia , Adenocarcinoma in Situ/patologia , Adulto , Feminino , Humanos , Recidiva Local de Neoplasia , Gravidez , Complicações Neoplásicas na Gravidez/patologia , Estudos Retrospectivos , Neoplasias do Colo do Útero/patologia
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