Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 556
Filtrar
Más filtros

Bases de datos
Tipo del documento
Intervalo de año de publicación
1.
Immunity ; 48(6): 1144-1159.e5, 2018 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-29884460

RESUMEN

PKCß-null (Prkcb-/-) mice are severely immunodeficient. Here we show that mice whose B cells lack PKCß failed to form germinal centers and plasma cells, which undermined affinity maturation and antibody production in response to immunization. Moreover, these mice failed to develop plasma cells in response to viral infection. At the cellular level, we have shown that Prkcb-/- B cells exhibited defective antigen polarization and mTORC1 signaling. While altered antigen polarization impaired antigen presentation and likely restricted the potential of GC development, defective mTORC1 signaling impaired metabolic reprogramming, mitochondrial remodeling, and heme biosynthesis in these cells, which altogether overwhelmingly opposed plasma cell differentiation. Taken together, our study reveals mechanistic insights into the function of PKCß as a key regulator of B cell polarity and metabolic reprogramming that instructs B cell fate.


Asunto(s)
Linfocitos B/inmunología , Diferenciación Celular/inmunología , Activación de Linfocitos/inmunología , Células Plasmáticas/inmunología , Proteína Quinasa C beta/inmunología , Animales , Hemo/biosíntesis , Ratones , Ratones Noqueados , Mitocondrias/inmunología , Mitocondrias/metabolismo , Células Plasmáticas/citología
2.
J Pathol ; 262(1): 90-104, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37929635

RESUMEN

Crosstalk between cancer and stellate cells is pivotal in pancreatic cancer, resulting in differentiation of stellate cells into myofibroblasts that drives tumour progression. To assess cooperative mechanisms in a 3D context, we generated chimeric spheroids using human and mouse cancer and stellate cells. Species-specific deconvolution of bulk-RNA sequencing data revealed cell type-specific transcriptomes underpinning invasion. This dataset highlighted stellate-specific expression of transcripts encoding the collagen-processing enzymes ADAMTS2 and ADAMTS14. Strikingly, loss of ADAMTS2 reduced, while loss of ADAMTS14 promoted, myofibroblast differentiation and invasion independently of their primary role in collagen-processing. Functional and proteomic analysis demonstrated that these two enzymes regulate myofibroblast differentiation through opposing roles in the regulation of transforming growth factor ß availability, acting on the protease-specific substrates, Serpin E2 and fibulin 2, for ADAMTS2 and ADAMTS14, respectively. Showcasing a broader complexity for these enzymes, we uncovered a novel regulatory axis governing malignant behaviour of the pancreatic cancer stroma. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Asunto(s)
Miofibroblastos , Neoplasias Pancreáticas , Animales , Humanos , Ratones , Proteínas ADAMTS/genética , Proteínas ADAMTS/metabolismo , Diferenciación Celular , Colágeno/metabolismo , Miofibroblastos/metabolismo , Neoplasias Pancreáticas/patología , Proteómica
3.
Chem Rev ; 122(10): 9307-9330, 2022 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-34766756

RESUMEN

The measurement and application of residual dipolar couplings (RDCs) in solution NMR studies of biological macromolecules has become well established over the past quarter of a century. Numerous methods for generating the requisite anisotropic orientational molecular distribution have been demonstrated, each with its specific strengths and weaknesses. In parallel, an enormous number of pulse schemes have been introduced to measure the many different types of RDCs, ranging from the most widely measured backbone amide 15N-1H RDCs, to 1H-1H RDCs and couplings between low-γ nuclei. Applications of RDCs range from structure validation and refinement to the determination of relative domain orientations, the measurement of backbone and domain motions, and de novo structure determination. Nevertheless, it appears that the power of the RDC methodology remains underutilized. This review aims to highlight the practical aspects of sample preparation and RDC measurement while describing some of the most straightforward applications that take advantage of the exceptionally precise information contained in such data. Some emphasis will be placed on more recent developments that enable the accurate measurement of RDCs in larger systems, which is key to the ongoing shift in focus of biological NMR spectroscopy from structure determination toward gaining improved understanding of how molecular flexibility drives protein function.


Asunto(s)
Proteínas , Espectroscopía de Resonancia Magnética/métodos , Resonancia Magnética Nuclear Biomolecular/métodos , Proteínas/química
4.
J Fish Biol ; 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39129462

RESUMEN

There is some evidence that the river migration success of Atlantic salmon smolts, on their first migration to sea, varies both spatially and temporally. However, we have only a poor understanding of what may be driving this variation. In this study, we used acoustic telemetry to quantify the spatial and temporal variations in river migration success in Atlantic salmon smolts on their first migration to sea. In total 4120 Atlantic salmon smolts migrating through 22 rivers in Scotland, England, Ireland, and Northern Ireland over multiple years were included in the study. Individuals were defined as successful migrants if detected leaving the river to enter marine waters. The results show significant temporal (up to 4 years) and spatial (river) variations in migration success, with overall between-river migration success varying from 3.4% to 97.0% and between years from 3.4% and 61.0%. Temporal variation in migration success was river specific, with some rivers being more temporally stable (exhibiting little variation between years) than others. Across all rivers and years, individual migration success was predicted positively by body condition and negatively by tag burden. The rate of migration success for a population (migration success standardized to a common river distance [proportion km-1]) was predicted by a number of environmental factors. The proportion of river catchment that comprised wetland and woodland positively predicted migration success, whereas the proportion of grassland and peatland in a catchment negatively predicted the rate of migration success. Although the mechanisms through which these effects may be operating were not directly examined in this study, we discuss some potential routes through which they may occur.

5.
Angew Chem Int Ed Engl ; 63(18): e202319578, 2024 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-38442302

RESUMEN

The development of inert, biocompatible chelation methods is required to harness the emerging positron emitting radionuclide 45Ti for radiopharmaceutical applications. Herein, we evaluate the Ti(IV)-coordination chemistry of four catechol-based, hexacoordinate chelators using synthetic, structural, computational, and radiochemical approaches. The siderophore enterobactin (Ent) and its synthetic mimic TREN-CAM readily form mononuclear Ti(IV) species in aqueous solution at neutral pH. Radiolabeling studies reveal that Ent and TREN-CAM form mononuclear complexes with the short-lived, positron-emitting radionuclide 45Ti(IV), and do not transchelate to plasma proteins in vitro and exhibit rapid renal clearance in naïve mice. These features guide efforts to target the 45Ti isotope to prostate cancer tissue through the design, synthesis, and evaluation of Ent-DUPA, a small molecule conjugate composed of a prostate specific membrane antigen (PSMA) targeting peptide and a monofunctionalized Ent scaffold. The [45Ti][Ti(Ent-DUPA)]2- complex forms readily at room temperature. In a tumor xenograft model in mice, selective tumor tissue accumulation (8±5 %, n=5), and low off-target uptake in other organs is observed. Overall, this work demonstrates targeted imaging with 45Ti(IV), provides a foundation for advancing the application of 45Ti in nuclear medicine, and reveals that Ent can be repurposed as a 45Ti-complexing cargo for targeted nuclear imaging applications.


Asunto(s)
Neoplasias de la Próstata , Sideróforos , Humanos , Masculino , Animales , Ratones , Sideróforos/química , Enterobactina/metabolismo , Titanio/química , Uso Fuera de lo Indicado , Neoplasias de la Próstata/metabolismo , Radioisótopos
6.
Biophys J ; 122(7): 1240-1253, 2023 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-36793214

RESUMEN

NADH and NADPH play key roles in the regulation of metabolism. Their endogenous fluorescence is sensitive to enzyme binding, allowing changes in cellular metabolic state to be determined using fluorescence lifetime imaging microscopy (FLIM). However, to fully uncover the underlying biochemistry, the relationships between their fluorescence and binding dynamics require greater understanding. Here we accomplish this through time- and polarization-resolved fluorescence and polarized two-photon absorption measurements. Two lifetimes result from binding of both NADH to lactate dehydrogenase and NADPH to isocitrate dehydrogenase. The composite fluorescence anisotropy indicates the shorter (1.3-1.6 ns) decay component to be accompanied by local motion of the nicotinamide ring, pointing to attachment solely via the adenine moiety. For the longer lifetime (3.2-4.4 ns), the nicotinamide conformational freedom is found to be fully restricted. As full and partial nicotinamide binding are recognized steps in dehydrogenase catalysis, our results unify photophysical, structural, and functional aspects of NADH and NADPH binding and clarify the biochemical processes that underlie their contrasting intracellular lifetimes.


Asunto(s)
NAD , Niacinamida , NAD/química , NAD/metabolismo , NADP , Fluorescencia , Catálisis
7.
Ann Surg Oncol ; 30(10): 6117-6124, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37479843

RESUMEN

BACKGROUND: Breast cancer surveillance programmes ensure early identification of recurrence which maximises overall survival. Programmes include annual clinical examination and radiological assessment. There remains debate around the value of annual clinical exam in diagnosing recurrent disease/second primaries. The aim was to assess diagnostic modalities for recurrent breast cancer with a focus on evaluating the role of annual clinical examination. PATIENTS AND METHODS: A prospectively maintained database from a symptomatic breast cancer service between 2010-2020 was reviewed. Patients with biopsy-proven recurrence/second breast primary were included. The primary outcome was the diagnostic modality by which recurrences/secondary breast cancers were observed. Diagnostic modalities included (i) self-detection by the patient, (ii) clinical examination by a breast surgeon or (iii) radiological assessment. RESULTS: A total of 233 patients were identified and, following application of exclusion criteria, a total of 140 patients were included. A total of 65/140 (46%) patients were diagnosed clinically, either by self-detection or clinical examination, while 75/140 (54%) were diagnosed radiologically. A total of 59/65 (91%) of patients clinically diagnosed with recurrence presented to the breast clinic after self-detection of an abnormality. Four (6%) patients had cognitive impairment and recurrence was diagnosed by a carer. Two (3%) patients were diagnosed with recurrence by a breast surgeon at clinical examination. The median time to recurrence in all patients was 48 months (range 2-263 months). CONCLUSION: Clinical examination provides little value in diagnosing recurrence (< 5%) and surveillance programmes may benefit from reduced focus on such a modality. Regular radiological assessment and ensuring patients have urgent/easy access to a breast clinic if they develop new symptoms/signs should be the focus of surveillance programmes.


Asunto(s)
Neoplasias de la Mama , Femenino , Humanos , Instituciones de Atención Ambulatoria , Biopsia , Neoplasias de la Mama/diagnóstico , Enfermedad Crónica , Estudios de Seguimiento
8.
Br J Surg ; 110(3): 324-332, 2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36512473

RESUMEN

BACKGROUND: Sentinel lymph node biopsy (SLNB) after neoadjuvant chemotherapy (NACT) in patients with breast cancer who are initially node-positive but convert to clinically/radiologically node-negative remains controversial. The primary aim was to assess pooled 5-year disease-free (DFS) and overall (OS) survival for patients who are initially node-positive but have a negative SLNB after NACT, and do not proceed to axillary lymph node dissection (ALND). METHODS: The study was performed using PRISMA guidelines. A systematic literature search of relevant databases was conducted. The Der Simonian-Laird and Cochran-Mantel-Haenszel methods were used to calculate weighted pooled estimates for OS and DFS for this group compared with patients who had NACT and proceeded to ALND after a negative or positive SLNB. RESULTS: Seven studies involving 915 patients who had a negative SLNB after NACT were included. Pooled estimates of 5-year DFS and OS in patients with a negative SLNB after NACT were 86 (95 per cent c.i. 82.1 to 90.3) and 93.1 (87.8 to 97.0) per cent respectively. Patients with a positive SLNB who underwent ALND had reduced 5-year DFS (OR 0.49, 95 per cent c.i. 0.35 to 0.69; P < 0.001) and OS (OR 0.41, 0.16 to 1.02; P = 0.06) compared with those who had a negative SLNB after NACT. There were no differences in DFS for patients who had a negative SLNB only compared with those undergoing ALND with a pCR (OR 1.65, 0.71 to 3.79; P = 0.24). CONCLUSION: Patients who are initially node-positive and who achieve a complete clinical/radiological axillary response after NACT with a subsequent negative SLNB have high rates of DFS and OS after 5 years. Patients with residual disease have significantly reduced DFS and further axillary treatment may still be warranted.


Asunto(s)
Neoplasias de la Mama , Ganglio Linfático Centinela , Humanos , Femenino , Biopsia del Ganglio Linfático Centinela/métodos , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/cirugía , Terapia Neoadyuvante , Escisión del Ganglio Linfático/métodos , Axila/patología , Ganglios Linfáticos/patología , Ganglio Linfático Centinela/cirugía , Ganglio Linfático Centinela/patología
9.
Inorg Chem ; 62(50): 20655-20665, 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-37523384

RESUMEN

The solution chemistry of the hydrolytic, early-transition-metal ions Ti4+ and Sc3+ represents a coordination chemistry challenge with important real-world implications, specifically in the context of 44Ti/44Sc and 45Ti/NatSc radiochemical separations. Unclear speciation of the solid and solution phases and tertiary mixtures of mineral acid, organic chelators, and solid supports are common confounds, necessitating tedious screening of multiple variables. Herein we describe how thermodynamic speciation data in solution informs the design of new solid-phase chelation approaches enabling separations of Ti4+ and Sc3+. The ligands catechol (benzene-1,2-diol) and deferiprone [3-hydroxy-1,2-dimethyl-4(1H)-pyridone] bind Ti4+ at significantly more acidic conditions (2-4 pH units) than Sc3+. Four chelating resins were synthesized using either catechol or deferiprone with two different solid supports. Of these, deferiprone appended to carboxylic acid polymer-functionalized silica (CA-Def) resin exhibited excellent binding affinity for Ti4+ across a wide range of HCl concentrations (1.0-0.001 M), whereas Sc3+ was only retained in dilute acidic conditions (0.01-0.001 M HCl). CA-Def resin produced separation factors of >100 (Ti/Sc) in 0.1-0.4 M HCl, and the corresponding Kd values (>1000) show strong retention of Ti4+. A model 44Ti/44Sc generator was produced, showing 65 ± 3% yield of 44Sc in 200 µL of 0.2 M HCl with a significant 44Ti breakthrough of 0.1%, precluding use in its current form. Attempts, however, removed natSc in loading fractions and a dilute (0.4 M HCl) wash and recovered 80% of the loaded 45Ti activity in 400 µL of 6 M HCl. The previously validated 45Ti chelator TREN-CAM was used for comparative proof-of-concept reactions with the CA-Def eluent (in HCl) and literature-reported hydroxamate-based resin eluents (in citric acid). CA-Def shows improved radiolabeling efficiency with an apparent molar activity (AMA) of 0.177 mCi nmol-1, exceeding the established methods (0.026 mCi nmol-1) and improving the separation and recovery of 45Ti for positron emission tomography imaging applications.

10.
Exp Brain Res ; 241(11-12): 2627-2643, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37737925

RESUMEN

To elucidate the underlying physiological mechanisms of muscle synergies, we investigated long-range functional connectivity by cortico-muscular (CMC), intermuscular (IMC) and cortico-synergy (CSC) coherence. Fourteen healthy participants executed an isometric upper limb task in synergy-tuned directions. Cortical activity was recorded using 32-channel electroencephalography (EEG) and muscle activity using 16-channel electromyography (EMG). Using non-negative matrix factorisation (NMF), we calculated muscle synergies from two different tasks. A preliminary multidirectional task was used to identify synergy-preferred directions (PDs). A subsequent coherence task, consisting of generating forces isometrically in the synergy PDs, was used to assess the functional connectivity properties of synergies. Overall, we were able to identify four different synergies from the multidirectional task. A significant alpha band IMC was consistently present in all extracted synergies. Moreover, IMC alpha band was higher between muscles with higher weights within a synergy. Interestingly, CSC alpha band was also significantly higher across muscles with higher weights within a synergy. In contrast, no significant CMC was found between the motor cortex area and synergy muscles. The presence of a shared input onto synergistic muscles within a synergy supports the idea of neurally derived muscle synergies that build human movement. Our findings suggest cortical modulation of some of the synergies and the consequential existence of shared input between muscles within cortically modulated synergies.


Asunto(s)
Músculo Esquelético , Extremidad Superior , Humanos , Músculo Esquelético/fisiología , Electromiografía , Movimiento/fisiología , Electroencefalografía
11.
J Pathol ; 257(4): 526-544, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35533046

RESUMEN

Cancer-associated fibroblasts (CAFs) have conflicting roles in the suppression and promotion of cancer. Current research focuses on targeting the undesirable properties of CAFs, while attempting to maintain tumour-suppressive roles. CAFs have been widely associated with primary or secondary therapeutic resistance, and strategies to modify CAF function have therefore largely focussed on their combination with existing therapies. Despite significant progress in preclinical studies, clinical translation of CAF targeted therapies has achieved limited success. Here we will review our emerging understanding of heterogeneous CAF populations in tumour biology and use examples from pancreatic ductal adenocarcinoma to explore why successful clinical targeting of protumourigenic CAF functions remains elusive. Single-cell technologies have allowed the identification of CAF subtypes with a differential impact on prognosis and response to therapy, but currently without clear consensus. Identification and pharmacological targeting of CAF subtypes associated with immunotherapy response offers new hope to expand clinical options for pancreatic cancer. Various CAF subtype markers may represent biomarkers for patient stratification, to obtain enhanced response with existing and emerging combinatorial therapeutic strategies. Thus, CAF subtyping is the next frontier in understanding and exploiting the tumour microenvironment for therapeutic benefit. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Asunto(s)
Fibroblastos Asociados al Cáncer , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Biomarcadores , Fibroblastos Asociados al Cáncer/patología , Carcinoma Ductal Pancreático/patología , Humanos , Neoplasias Pancreáticas/patología , Microambiente Tumoral , Neoplasias Pancreáticas
12.
Colorectal Dis ; 25(8): 1671-1678, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37431983

RESUMEN

AIM: The aim of this study was to translate the Dutch patient-reported outcome measure-haemorrhoidal impact and satisfaction score (PROM-HISS) to English and perform a cross-cultural validation. METHOD: The ISPOR good practice guidelines for the cross-cultural validation of PROMs were followed and included two steps: (1) Two forward and two backward translations. The forward translation concerned the translation from the source language (Dutch) to the target language (English), performed by two independent English speakers, one medical doctor and one nonmedical. Subsequently, a discussion about discrepancies in the reconciled version was performed by a stakeholder group. (2) Cognitive interviews were held with patients with haemorrhoidal disease (HD), probing the comprehensibility and comprehensiveness of the PROM-HISS. RESULTS: Discrepancies in the reconciled forward translation concerned the terminology of HD symptoms. Furthermore, special attention was paid to the response options, ranging from "not at all", indicating minor symptoms, to "a lot", implying many symptoms. Consensus among the stakeholder group about the final version of the translated PROM-HISS was reached. Interviews were conducted with 10 native English-speaking HD patients (30% female), with a mean age of 44 years (24-83) and primarily diagnosed with grade II HD (80%). The mean time to complete the PROM-HISS was 1 min 43 s. Patients showed a good understanding of the questions and response options, found all items relevant and did not miss important symptoms or topics. CONCLUSION: The translated English language PROM-HISS is a valid tool to assess symptoms of HD, its impact on daily activities and patient satisfaction with HD treatment.


Asunto(s)
Comparación Transcultural , Satisfacción del Paciente , Humanos , Femenino , Adulto , Masculino , Reproducibilidad de los Resultados , Lenguaje , Traducciones , Medición de Resultados Informados por el Paciente , Satisfacción Personal , Encuestas y Cuestionarios
13.
World J Surg ; 47(4): 922-927, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36564560

RESUMEN

BACKGROUND: Clinical acumen and experience are critical in the diagnosis of the commonest surgical emergency, acute appendicitis. However, there is an increasing focus on haematological and radiological parameters in reaching the diagnosis of appendicitis, which can negate the importance of clinical findings. The aim was to assess the accuracy of each grade of the surgical team in diagnosing acute appendicitis using clinical acuity alone and compare them to each other as well as validated predictive scores. METHODS: A prospective single-centre study was performed over a six-month period (Dec 2020-May 2021). All patients presenting to the emergency department with right iliac fossa pain were included. RESULTS: A total of 180 patients were included of whom 35% were male. Mean age was 36.2 years (range 16-91). 51.1% had a final diagnosis of appendicitis, of which 91.3% were managed surgically and 8.7% were treated conservatively with antibiotics. Consultants were correct in their prediction of appendicitis in 84.6% of cases (females-83.4%, males-86.6%). Registrars accurately predicted appendicitis in 82.2% of patients (females-80.3%, males-85.7%), whilst house officers (SHOs) and interns were right in 73.8% (females-69.2%, males-82.5%) and 72.7% (females-66.6%, males-83.9%) of cases, respectively. In patients with a histological or radiological diagnosis of appendicitis, the mean Acute Inflammatory Response Score and Acute Appendicitis Score were 7.0 (high risk ≥ 9) and 12.5 (high risk ≥ 16), respectively. Clinicians had superior diagnostic accuracy when compared with both the clinical scores used. CONCLUSION: Seniority was associated with improved diagnostic accuracy in clinically predicting acute appendicitis. This study showed that the clinical judgement of experienced surgeons is more reliable than clinical scores in the diagnosis of appendicitis.


Asunto(s)
Apendicitis , Femenino , Humanos , Masculino , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Estudios Prospectivos , Apendicitis/diagnóstico , Apendicitis/cirugía , Servicio de Urgencia en Hospital , Antibacterianos , Inflamación , Enfermedad Aguda , Apendicectomía
14.
Biochem J ; 479(13): 1467-1486, 2022 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-35730579

RESUMEN

The protein kinase PKN2 is required for embryonic development and PKN2 knockout mice die as a result of failure in the expansion of mesoderm, cardiac development and neural tube closure. In the adult, cardiomyocyte PKN2 and PKN1 (in combination) are required for cardiac adaptation to pressure-overload. The specific role of PKN2 in contractile cardiomyocytes during development and its role in the adult heart remain to be fully established. We used mice with cardiomyocyte-directed knockout of PKN2 or global PKN2 haploinsufficiency to assess cardiac development and function using high resolution episcopic microscopy, MRI, micro-CT and echocardiography. Biochemical and histological changes were also assessed. Cardiomyocyte-directed PKN2 knockout embryos displayed striking abnormalities in the compact myocardium, with frequent myocardial clefts and diverticula, ventricular septal defects and abnormal heart shape. The sub-Mendelian homozygous knockout survivors developed cardiac failure. RNASeq data showed up-regulation of PKN2 in patients with dilated cardiomyopathy, suggesting an involvement in adult heart disease. Given the rarity of homozygous survivors with cardiomyocyte-specific deletion of PKN2, the requirement for PKN2 in adult mice was explored using the constitutive heterozygous PKN2 knockout. Cardiac hypertrophy resulting from hypertension induced by angiotensin II was reduced in these haploinsufficient PKN2 mice relative to wild-type littermates, with suppression of cardiomyocyte hypertrophy and cardiac fibrosis. It is concluded that cardiomyocyte PKN2 is essential for heart development and the formation of compact myocardium and is also required for cardiac hypertrophy in hypertension. Thus, PKN signalling may offer therapeutic options for managing congenital and adult heart diseases.


Asunto(s)
Cardiomiopatías , Hipertensión , Proteína Quinasa C/metabolismo , Angiotensina II/metabolismo , Angiotensina II/farmacología , Animales , Cardiomegalia/metabolismo , Cardiomiopatías/metabolismo , Cardiomiopatías/patología , Femenino , Hipertensión/metabolismo , Hipertensión/patología , Ratones , Ratones Noqueados , Miocardio/metabolismo , Miocitos Cardíacos/metabolismo , Embarazo
15.
Int J Mol Sci ; 24(16)2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37628794

RESUMEN

Our understanding of the molecular mechanisms underlying cancer development and evolution have evolved rapidly over recent years, and the variation from one patient to another is now widely recognized. Consequently, one-size-fits-all approaches to the treatment of cancer have been superseded by precision medicines that target specific disease characteristics, promising maximum clinical efficacy, minimal safety concerns, and reduced economic burden. While precision oncology has been very successful in the treatment of some tumors with specific characteristics, a large number of patients do not yet have access to precision medicines for their disease. The success of next-generation precision oncology depends on the discovery of new actionable disease characteristics, rapid, accurate, and comprehensive diagnosis of complex phenotypes within each patient, novel clinical trial designs with improved response rates, and worldwide access to novel targeted anticancer therapies for all patients. This review outlines some of the current technological trends, and highlights some of the complex multidisciplinary efforts that are underway to ensure that many more patients with cancer will be able to benefit from precision oncology in the near future.


Asunto(s)
Neoplasias , Humanos , Neoplasias/tratamiento farmacológico , Medicina de Precisión , Oncología Médica , Estudios Interdisciplinarios , Fenotipo
16.
Aust Crit Care ; 36(1): 114-118, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35016842

RESUMEN

BACKGROUND: The use of extracorporeal membrane oxygenation (ECMO) is increasing in the management of critical care patients. ECMO service delivery requires an organisation-supported approach to ensure appropriate resources to deliver training, equipment, capacity, staffing, and the required model of care for quality care delivery. The aim of this nested substudy was to explore challenges specific to nursing staff in ECMO services in Australian intensive care units. METHODS: This was a nested substudy within a qualitative study using semistructured focus group discussions conducted with 83 health professionals, which included 40 nurses. There were 14 focus groups across 14 ECMO centres participating in the binational ECMO (EXCEL) registry of Australia and New Zealand. An inductive thematic analysis focused on the nurse's experiences of the barriers and facilitators for nursing in providing an ECMO service. RESULTS: Four themes emerged relating to the nurse's experience of implementing ECMO services: workforce requirements, workload demands, models of care, and level of experience. The complexity and intensity of caring for ECMO patients may need to be considered an additional factor in the burnout in critical care nurses. Current nursing ratios and responsibilities in critical care need to be considered, with the opportunity for the development of specialist advanced practitioner nursing roles. CONCLUSION: This study highlights the challenges for nursing in providing ECMO services in the intensive care setting. The complexity and intensity of ECMO is challenging and leads to concerns regarding burnout and workforce preparedness. New models of care need to be considered to mitigate the barriers for nursing identified across ECMO centres.


Asunto(s)
Agotamiento Profesional , Oxigenación por Membrana Extracorpórea , Personal de Enfermería , Humanos , Australia , Unidades de Cuidados Intensivos , Recursos Humanos
17.
Int J Cancer ; 151(3): 422-434, 2022 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-35411939

RESUMEN

Abiraterone acetate plus prednisolone (AAP) previously demonstrated improved survival in STAMPEDE, a multiarm, multistage platform trial in men starting long-term hormone therapy for prostate cancer. This long-term analysis in metastatic patients was planned for 3 years after the first results. Standard-of-care (SOC) was androgen deprivation therapy. The comparison randomised patients 1:1 to SOC-alone with or without daily abiraterone acetate 1000 mg + prednisolone 5 mg (SOC + AAP), continued until disease progression. The primary outcome measure was overall survival. Metastatic disease risk group was classified retrospectively using baseline CT and bone scans by central radiological review and pathology reports. Analyses used Cox proportional hazards and flexible parametric models, accounting for baseline stratification factors. One thousand and three patients were contemporaneously randomised (November 2011 to January 2014): median age 67 years; 94% newly-diagnosed; metastatic disease risk group: 48% high, 44% low, 8% unassessable; median PSA 97 ng/mL. At 6.1 years median follow-up, 329 SOC-alone deaths (118 low-risk, 178 high-risk) and 244 SOC + AAP deaths (75 low-risk, 145 high-risk) were reported. Adjusted HR = 0.60 (95% CI: 0.50-0.71; P = 0.31 × 10-9 ) favoured SOC + AAP, with 5-years survival improved from 41% SOC-alone to 60% SOC + AAP. This was similar in low-risk (HR = 0.55; 95% CI: 0.41-0.76) and high-risk (HR = 0.54; 95% CI: 0.43-0.69) patients. Median and current maximum time on SOC + AAP was 2.4 and 8.1 years. Toxicity at 4 years postrandomisation was similar, with 16% patients in each group reporting grade 3 or higher toxicity. A sustained and substantial improvement in overall survival of all metastatic prostate cancer patients was achieved with SOC + abiraterone acetate + prednisolone, irrespective of metastatic disease risk group.


Asunto(s)
Neoplasias de la Próstata Resistentes a la Castración , Neoplasias de la Próstata , Acetato de Abiraterona/uso terapéutico , Anciano , Antagonistas de Andrógenos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Estudios de Seguimiento , Hormonas , Humanos , Masculino , Prednisolona/uso terapéutico , Prednisona/uso terapéutico , Neoplasias de la Próstata/patología , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Estudios Retrospectivos , Resultado del Tratamiento
18.
Chembiochem ; 23(19): e202200471, 2022 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-35972230

RESUMEN

The 68-kDa homodimeric 3C-like protease of SARS-CoV-2, Mpro (3CLpro /Nsp5), is a key antiviral drug target. NMR spectroscopy of this large system proved challenging and resonance assignments have remained incomplete. Here we present the near-complete (>97 %) backbone assignments of a C145A variant of Mpro (Mpro C145A ) both with, and without, the N-terminal auto-cleavage substrate sequence, in its native homodimeric state. We also present SILLY (Selective Inversion of thioL and Ligand for NOESY), a simple yet effective pseudo-3D NMR experiment that utilizes NOEs to identify interactions between Cys-thiol or aliphatic protons, and their spatially proximate backbone amides in a perdeuterated protein background. High protection against hydrogen exchange is observed for 10 of the 11 thiol groups in Mpro C145A , even those that are partially accessible to solvent. A combination of SILLY methods and high-resolution triple-resonance NMR experiments reveals site-specific interactions between Mpro , its substrate peptides, and other ligands, which present opportunities for competitive binding studies in future drug design efforts.


Asunto(s)
COVID-19 , Protones , Amidas , Antivirales/química , Proteasas 3C de Coronavirus , Cisteína Endopeptidasas/metabolismo , Humanos , Ligandos , Espectroscopía de Resonancia Magnética , Péptidos/metabolismo , Inhibidores de Proteasas , SARS-CoV-2 , Solventes , Compuestos de Sulfhidrilo
19.
Phys Rev Lett ; 129(19): 195002, 2022 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-36399755

RESUMEN

The application of an external 26 Tesla axial magnetic field to a D_{2} gas-filled capsule indirectly driven on the National Ignition Facility is observed to increase the ion temperature by 40% and the neutron yield by a factor of 3.2 in a hot spot with areal density and temperature approaching what is required for fusion ignition [1]. The improvements are determined from energy spectral measurements of the 2.45 MeV neutrons from the D(d,n)^{3}He reaction, and the compressed central core B field is estimated to be ∼4.9 kT using the 14.1 MeV secondary neutrons from the D(T,n)^{4}He reactions. The experiments use a 30 kV pulsed-power system to deliver a ∼3 µs current pulse to a solenoidal coil wrapped around a novel high-electrical-resistivity AuTa_{4} hohlraum. Radiation magnetohydrodynamic simulations are consistent with the experiment.

20.
Nat Chem Biol ; 16(1): 24-30, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31686030

RESUMEN

Lysostaphin is a bacteriolytic enzyme targeting peptidoglycan, the essential component of the bacterial cell envelope. It displays a very potent and specific activity toward staphylococci, including methicillin-resistant Staphylococcus aureus. Lysostaphin causes rapid cell lysis and disrupts biofilms, and is therefore a therapeutic agent of choice to eradicate staphylococcal infections. The C-terminal SH3b domain of lysostaphin recognizes peptidoglycans containing a pentaglycine crossbridge and has been proposed to drive the preferential digestion of staphylococcal cell walls. Here we elucidate the molecular mechanism underpinning recognition of staphylococcal peptidoglycan by the lysostaphin SH3b domain. We show that the pentaglycine crossbridge and the peptide stem are recognized by two independent binding sites located on opposite sides of the SH3b domain, thereby inducing a clustering of SH3b domains. We propose that this unusual binding mechanism allows synergistic and structurally dynamic recognition of S. aureus peptidoglycan and underpins the potent bacteriolytic activity of this enzyme.


Asunto(s)
Lisostafina/química , Peptidoglicano/química , Staphylococcus aureus/química , Bacteriólisis/efectos de los fármacos , Biopelículas , Pared Celular/química , Cromatografía Líquida de Alta Presión , Análisis Mutacional de ADN , Glicina/química , Ligandos , Espectroscopía de Resonancia Magnética , Mutagénesis Sitio-Dirigida , Péptidos/química , Unión Proteica , Dominios Proteicos , Proteínas Recombinantes/química , Dominios Homologos src
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA