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1.
Kidney Int ; 105(5): 1058-1076, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38364990

RESUMO

Pathogenic variants in solute carrier family 34, member 3 (SLC34A3), the gene encoding the sodium-dependent phosphate cotransporter 2c (NPT2c), cause hereditary hypophosphatemic rickets with hypercalciuria (HHRH). Here, we report a pooled analysis of clinical and laboratory records of 304 individuals from 145 kindreds, including 20 previously unreported HHRH kindreds, in which two novel SLC34A3 pathogenic variants were identified. Compound heterozygous/homozygous carriers show above 90% penetrance for kidney and bone phenotypes. The biochemical phenotype for heterozygous carriers is intermediate with decreased serum phosphate, tubular reabsorption of phosphate (TRP (%)), fibroblast growth factor 23, and intact parathyroid hormone, but increased serum 1,25-dihydroxy vitamin D, and urine calcium excretion causing idiopathic hypercalciuria in 38%, with bone phenotypes still observed in 23% of patients. Oral phosphate supplementation is the current standard of care, which typically normalizes serum phosphate. However, although in more than half of individuals this therapy achieves correction of hypophosphatemia it fails to resolve the other outcomes. The American College of Medical Genetics and Genomics score correlated with functional analysis of frequent SLC34A3 pathogenic variants in vitro and baseline disease severity. The number of mutant alleles and baseline TRP (%) were identified as predictors for kidney and bone phenotypes, baseline TRP (%) furthermore predicted response to therapy. Certain SLC34A3/NPT2c pathogenic variants can be identified with partial responses to therapy, whereas with some overlap, others present only with kidney phenotypes and a third group present only with bone phenotypes. Thus, our report highlights important novel clinical aspects of HHRH and heterozygous carriers, raises awareness to this rare group of disorders and can be a foundation for future studies urgently needed to guide therapy of HHRH.


Assuntos
Raquitismo Hipofosfatêmico Familiar , Hipofosfatemia , Humanos , Raquitismo Hipofosfatêmico Familiar/complicações , Raquitismo Hipofosfatêmico Familiar/diagnóstico , Raquitismo Hipofosfatêmico Familiar/tratamento farmacológico , Hipercalciúria/diagnóstico , Hipercalciúria/tratamento farmacológico , Hipercalciúria/genética , Rim/metabolismo , Fosfatos , Proteínas Cotransportadoras de Sódio-Fosfato Tipo IIc/genética , Proteínas Cotransportadoras de Sódio-Fosfato Tipo IIc/metabolismo
2.
Cell Mol Life Sci ; 79(10): 513, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36097202

RESUMO

The link between cancer and aberrant glycosylation has recently become evident. Glycans and their altered forms, known as tumour-associated carbohydrate antigens (TACAs), are diverse, complex and difficult to target therapeutically. Lectins are naturally occurring glycan-binding proteins  that offer a unique opportunity to recognise TACAs. T cells expressing chimeric antigen receptors (CARs) have proven to be a successful immunotherapy against leukaemias, but so far have shown limited success in solid tumours. We developed a panel of lectin-CARs that recognise the glycosphingolipid globotriaosylceramide (Gb3), which is overexpressed in various cancers, such as Burkitt's lymphoma, colorectal, breast and pancreatic. We have selected the following lectins: Shiga toxin's B-subunit from Shigella dysenteriae, LecA from Pseudomonas aeruginosa, and the engineered lectin Mitsuba from Mytilus galloprovincialis as antigen-binding domains and fused them to a well-known second-generation CAR. The Gb3-binding lectin-CARs have demonstrated target-specific cytotoxicity against Burkitt's lymphoma-derived cell lines as well as solid tumour cells from colorectal and triple-negative breast cancer. Our findings reveal the big potential of lectin-based CARs as therapeutical applications to target Gb3 and other TACAs expressed in haematological malignancies and solid tumours.


Assuntos
Linfoma de Burkitt , Neoplasias Colorretais , Receptores de Antígenos Quiméricos , Linfoma de Burkitt/metabolismo , Linfoma de Burkitt/terapia , Humanos , Lectinas/metabolismo , Polissacarídeos/metabolismo , Linfócitos T
3.
Small ; 18(6): e2105157, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34859962

RESUMO

Controlling the time and dose of nanoparticulate drug delivery by administration of small molecule drugs holds promise for efficient and safer therapies. This study describes a versatile approach of exploiting antibody-ligand interactions for the design of small molecule-responsive nanocarrier and nanocomposite systems. For this purpose, antibody fragments (scFvs) specific for two distinct small molecule ligands are designed. Subsequently, the surface of nanoparticles (liposomes or adeno-associated viral vectors, AAVs) is modified with these ligands, serving as anchor points for scFv binding. By modifying the scFvs with polymer tails, they can act as a non-covalently bound shielding layer, which is recruited to the anchor points on the nanoparticle surface and prevents interactions with cultured mammalian cells. Administration of an excess of the respective ligand triggers competitive displacement of the shielding layer from the nanoparticle surface and restores nanoparticle-cell interactions. The same principle is applied for developing hydrogel depots that can release integrated AAVs or liposomes in response to small molecule ligands. The liberated nanoparticles subsequently deliver their cargoes to cells. In summary, the utilization of different antibody-ligand interactions, different nanoparticles, and different release systems validates the versatility of the design concept described herein.


Assuntos
Lipossomos , Nanopartículas , Animais , Vetores Genéticos , Ligantes , Mamíferos , Nanopartículas/química , Polímeros
4.
Proc Natl Acad Sci U S A ; 116(41): 20700-20706, 2019 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-31527267

RESUMO

Microbial invasion into the intestinal mucosa after allogeneic hematopoietic cell transplantation (allo-HCT) triggers neutrophil activation and requires antibiotic interventions to prevent sepsis. However, antibiotics lead to a loss of microbiota diversity, which is connected to a higher incidence of acute graft-versus-host disease (aGVHD). Antimicrobial therapies that eliminate invading bacteria and reduce neutrophil-mediated damage without reducing the diversity of the microbiota are therefore highly desirable. A potential solution would be the use of antimicrobial antibodies that target invading pathogens, ultimately leading to their elimination by innate immune cells. In a mouse model of aGVHD, we investigated the potency of active and passive immunization against the conserved microbial surface polysaccharide poly-N-acetylglucosamine (PNAG) that is expressed on numerous pathogens. Treatment with monoclonal or polyclonal antibodies to PNAG (anti-PNAG) or vaccination against PNAG reduced aGVHD-related mortality. Anti-PNAG treatment did not change the intestinal microbial diversity as determined by 16S ribosomal DNA sequencing. Anti-PNAG treatment reduced myeloperoxidase activation and proliferation of neutrophil granulocytes (neutrophils) in the ileum of mice developing GVHD. In vitro, anti-PNAG treatment showed high antimicrobial activity. The functional role of neutrophils was confirmed by using neutrophil-deficient LysMcreMcl1fl/fl mice that had no survival advantage under anti-PNAG treatment. In summary, the control of invading bacteria by anti-PNAG treatment could be a novel approach to reduce the uncontrolled neutrophil activation that promotes early GVHD and opens a new avenue to interfere with aGVHD without affecting commensal intestinal microbial diversity.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Bactérias/imunologia , Doença Enxerto-Hospedeiro/prevenção & controle , Imunização Passiva/métodos , Intestinos/imunologia , Ativação de Neutrófilo/imunologia , Polissacarídeos Bacterianos/antagonistas & inibidores , Animais , Anticorpos Monoclonais/imunologia , Bactérias/classificação , Bactérias/efeitos dos fármacos , Feminino , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/patologia , Intestinos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Ativação de Neutrófilo/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Polissacarídeos Bacterianos/imunologia
5.
Urol Int ; 106(5): 431-439, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35144260

RESUMO

BACKGROUND: Focal therapy (FT) is an option to treat localized prostate cancer (PCa) and preserve healthy prostate tissue in order to reduce known side effects from primary whole-gland treatment. The available FT modalities are manifold. Until now, national and international PCa guidelines have been cautious to propose recommendations regarding FT treatment since data from prospective controlled trials are lacking for most FT modalities. Moreover, none of the international guidelines provides a separate section on FT. In this purpose, we provide a synopsis of the consensus-based German S3 guidelines for a possible international use. SUMMARY: The recently published update of the German S3 guidelines, an evidence- and consensus-based guideline, provides a section on FT with recommendations for diagnostic work-up, indications, modalities, and follow-up. This section consists of 12 statements and recommendations for FT in the treatment of localized PCa. KEY MESSAGE: The German S3 guidelines on PCa are the first to incorporate recommendations for FT based on evidence and expert consensus including indication criteria for FT, pretreatment, and follow-up diagnostic pathways as well as an extended overview of FT techniques and the current supportive evidence.


Assuntos
Neoplasias da Próstata , Crioterapia , Humanos , Masculino , Estudos Prospectivos , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/terapia
6.
PLoS Biol ; 16(8): e2005886, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30096135

RESUMO

Circadian clocks are fundamental physiological regulators of energy homeostasis, but direct transcriptional targets of the muscle clock machinery are unknown. To understand how the muscle clock directs rhythmic metabolism, we determined genome-wide binding of the master clock regulators brain and muscle ARNT-like protein 1 (BMAL1) and REV-ERBα in murine muscles. Integrating occupancy with 24-hr gene expression and metabolomics after muscle-specific loss of BMAL1 and REV-ERBα, here we unravel novel molecular mechanisms connecting muscle clock function to daily cycles of lipid and protein metabolism. Validating BMAL1 and REV-ERBα targets using luciferase assays and in vivo rescue, we demonstrate how a major role of the muscle clock is to promote diurnal cycles of neutral lipid storage while coordinately inhibiting lipid and protein catabolism prior to awakening. This occurs by BMAL1-dependent activation of Dgat2 and REV-ERBα-dependent repression of major targets involved in lipid metabolism and protein turnover (MuRF-1, Atrogin-1). Accordingly, muscle-specific loss of BMAL1 is associated with metabolic inefficiency, impaired muscle triglyceride biosynthesis, and accumulation of bioactive lipids and amino acids. Taken together, our data provide a comprehensive overview of how genomic binding of BMAL1 and REV-ERBα is related to temporal changes in gene expression and metabolite fluctuations.


Assuntos
Fatores de Transcrição ARNTL/fisiologia , Relógios Circadianos/fisiologia , Músculo Esquelético/fisiologia , Aminoácidos/metabolismo , Aminoácidos/fisiologia , Animais , Proteínas CLOCK/genética , Ritmo Circadiano/genética , Expressão Gênica , Homeostase , Humanos , Metabolismo dos Lipídeos/fisiologia , Lipídeos , Camundongos , Camundongos Knockout , RNA Mensageiro/metabolismo
7.
J Struct Biol ; 209(3): 107448, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31926272

RESUMO

Calcium biominerals occur in all major animal phyla, and through biomolecular control, exhibit such diverse structures as exoskeletons, shells, bones, teeth and earstones (otoliths). Determining the three-dimensional expression of key biomineral proteins, however, has proven challenging as typical protein identification methods either lose spatial resolution during dissolution of the mineral phase or are costly and limited to two-dimensional expression of high abundance proteins. Here we present a modification of the CLARITY and ACT-PRESTO protocols to visualize and confirm, for the first time, the timing of expression and function of two key regulators of biomineralization.


Assuntos
Biomineralização , Minerais/química , Proteínas Associadas à Matriz Nuclear/ultraestrutura , Proteínas/ultraestrutura , Exoesqueleto/química , Exoesqueleto/ultraestrutura , Animais , Cálcio/química , Carbonato de Cálcio , Imageamento Tridimensional/métodos , Proteínas Associadas à Matriz Nuclear/química , Dente/química , Dente/ultraestrutura
8.
Blood ; 131(16): 1858-1869, 2018 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-29463561

RESUMO

Conditioning-induced damage of the intestinal tract plays a critical role during the onset of acute graft-versus-host disease (GVHD). Therapeutic interference with these early events of GVHD is difficult, and currently used immunosuppressive drugs mainly target donor T cells. However, not donor T cells but neutrophils reach the sites of tissue injury first, and therefore could be a potential target for GVHD prevention. A detailed analysis of neutrophil fate during acute GVHD and the effect on T cells is difficult because of the short lifespan of this cell type. By using a novel photoconverter reporter system, we show that neutrophils that had been photoconverted in the ileum postconditioning later migrated to mesenteric lymph nodes (mLN). This neutrophil migration was dependent on the intestinal microflora. In the mLN, neutrophils colocalized with T cells and presented antigen on major histocompatibility complex (MHC)-II, thereby affecting T cell expansion. Pharmacological JAK1/JAK2 inhibition reduced neutrophil influx into the mLN and MHC-II expression, thereby interfering with an early event in acute GVHD pathogenesis. In agreement with this finding, neutrophil depletion reduced acute GVHD. We conclude that neutrophils are attracted to the ileum, where the intestinal barrier is disrupted, and then migrate to the mLN, where they participate in alloantigen presentation. JAK1/JAK2-inhibition can interfere with this process, which provides a potential therapeutic strategy to prevent early events of tissue damage-related innate immune cell activation and, ultimately, GVHD.


Assuntos
Comunicação Celular/imunologia , Doença Enxerto-Hospedeiro/imunologia , Íleo/imunologia , Linfonodos/imunologia , Mesentério/imunologia , Neutrófilos/imunologia , Doença Aguda , Animais , Comunicação Celular/efeitos dos fármacos , Comunicação Celular/genética , Doença Enxerto-Hospedeiro/tratamento farmacológico , Doença Enxerto-Hospedeiro/genética , Doença Enxerto-Hospedeiro/patologia , Íleo/patologia , Janus Quinase 1/antagonistas & inibidores , Janus Quinase 1/genética , Janus Quinase 1/imunologia , Janus Quinase 2/antagonistas & inibidores , Janus Quinase 2/genética , Janus Quinase 2/imunologia , Linfonodos/patologia , Mesentério/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Infiltração de Neutrófilos/efeitos dos fármacos , Infiltração de Neutrófilos/genética , Infiltração de Neutrófilos/imunologia , Neutrófilos/patologia , Inibidores de Proteínas Quinases/farmacologia
9.
Circulation ; 137(4): 354-363, 2018 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-29138293

RESUMO

BACKGROUND: Efforts to safely reduce length of stay for emergency department patients with symptoms suggestive of acute coronary syndrome (ACS) have had mixed success. Few system-wide efforts affecting multiple hospital emergency departments have ever been evaluated. We evaluated the effectiveness of a nationwide implementation of clinical pathways for potential ACS in disparate hospitals. METHODS: This was a multicenter pragmatic stepped-wedge before-and-after trial in 7 New Zealand acute care hospitals with 31 332 patients investigated for suspected ACS with serial troponin measurements. The implementation was a clinical pathway for the assessment of patients with suspected ACS that included a clinical pathway document in paper or electronic format, structured risk stratification, specified time points for electrocardiographic and serial troponin testing within 3 hours of arrival, and directions for combining risk stratification and electrocardiographic and troponin testing in an accelerated diagnostic protocol. Implementation was monitored for >4 months and compared with usual care over the preceding 6 months. The main outcome measure was the odds of discharge within 6 hours of presentation RESULTS: There were 11 529 participants in the preimplementation phase (range, 284-3465) and 19 803 in the postimplementation phase (range, 395-5039). Overall, the mean 6-hour discharge rate increased from 8.3% (range, 2.7%-37.7%) to 18.4% (6.8%-43.8%). The odds of being discharged within 6 hours increased after clinical pathway implementation. The odds ratio was 2.4 (95% confidence interval, 2.3-2.6). In patients without ACS, the median length of hospital stays decreased by 2.9 hours (95% confidence interval, 2.4-3.4). For patients discharged within 6 hours, there was no change in 30-day major adverse cardiac event rates (0.52% versus 0.44%; P=0.96). In these patients, no adverse event occurred when clinical pathways were correctly followed. CONCLUSIONS: Implementation of clinical pathways for suspected ACS reduced the length of stay and increased the proportions of patients safely discharged within 6 hours. CLINICAL TRIAL REGISTRATION: URL: https://www.anzctr.org.au/ (Australian and New Zealand Clinical Trials Registry). Unique identifier: ACTRN12617000381381.


Assuntos
Síndrome Coronariana Aguda/diagnóstico , Serviço Hospitalar de Cardiologia/normas , Procedimentos Clínicos/normas , Serviço Hospitalar de Emergência/normas , Hospitalização , Melhoria de Qualidade/normas , Indicadores de Qualidade em Assistência à Saúde/normas , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/epidemiologia , Síndrome Coronariana Aguda/terapia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Tomada de Decisão Clínica , Eletrocardiografia , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Nova Zelândia/epidemiologia , Valor Preditivo dos Testes , Prevalência , Prognóstico , Medição de Risco , Fatores de Risco , Fatores de Tempo , Troponina/sangue
11.
Nucleic Acids Res ; 44(D1): D509-14, 2016 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-26615197

RESUMO

Over the last decades, the genus Streptomyces has stirred huge interest in the scientific community as a source of bioactive compounds. The majority of all known antibiotics is isolated from these bacterial strains, as well as a variety of other drugs such as antitumor agents, immunosuppressants and antifungals. To the best of our knowledge, StreptomeDB was the first database focusing on compounds produced by streptomycetes. The new version presented herein represents a major step forward: its content has been increased to over 4000 compounds and more than 2500 host organisms. In addition, we have extended the background information and included hundreds of new manually curated references to literature. The latest update features a unique scaffold-based navigation system, which enables the exploration of the chemical diversity of StreptomeDB on a structural basis. We have included a phylogenetic tree, based on 16S rRNA sequences, which comprises more than two-thirds of the included host organisms. It enables visualizing the frequency, appearance, and persistence of compounds and scaffolds in an evolutionary context. Additionally, we have included predicted MS- and NMR-spectra of thousands of compounds for assignment of experimental data. The database is freely accessible via http://www.pharmaceutical-bioinformatics.org/streptomedb.


Assuntos
Produtos Biológicos/química , Bases de Dados de Compostos Químicos , Streptomyces/química , Produtos Biológicos/metabolismo , Filogenia , Streptomyces/classificação , Streptomyces/genética , Streptomyces/metabolismo
12.
Postgrad Med J ; 94(1109): 143-150, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29122928

RESUMO

INTRODUCTION: Use of the WHO surgical safety checklist is consistently recognised to reduce harm caused by human error during the perioperative period. Inconsistent engagement is considered to contribute to persistence of surgical Never Events in the National Health Service. Most medical and nursing graduates will join teams responsible for the perioperative care of patients, therefore appropriate undergraduate surgical safety training is needed. AIMS: To investigate UK medical and nursing undergraduate experience of the surgical safety checklist training. METHODS: An eight-item electronic questionnaire was distributed electronically to 32 medical schools and 72 nursing schools. Analysis was conducted for the two cohorts, and responses from final year students were included. RESULTS: 87/224 (38.8%) of medical students received teaching on the surgical safety checklist, compared with 380/711 (52.0%) of nursing students. 172/224 (76.8%) of medical students and 489/711 (66.9%) of nursing students understood its purpose and 8/224 (3.6%) medical students and 54/711 (7.4%) nursing students reported never being included in the Time Out. After adjusting for confounding factors, provision of formal teaching in checklist use increased understanding significantly (OR 50.39 (14.07 to 325.79, P<0.001)), as did routine student involvement in time outs (OR 5.72 (2.36 to 14.58, P<0.001)). DISCUSSION: Knowledge of perioperative patient safety systems and the ability to participate in safety protocols are important skills that should be formally taught at the undergraduate level. Results of this study show that UK undergraduate surgical safety checklist training does not meet the minimum standards set by the WHO.


Assuntos
Lista de Checagem , Assistência Perioperatória , Estudantes de Medicina/psicologia , Estudantes de Enfermagem/psicologia , Adulto , Educação de Graduação em Medicina/métodos , Educação em Enfermagem/métodos , Feminino , Humanos , Masculino , Erros Médicos/prevenção & controle , Assistência Perioperatória/educação , Assistência Perioperatória/métodos , Assistência Perioperatória/enfermagem , Gestão da Segurança/métodos , Procedimentos Cirúrgicos Operatórios/métodos , Inquéritos e Questionários , Ensino , Reino Unido
13.
Educ Health (Abingdon) ; 30(1): 75-78, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28707641

RESUMO

BACKGROUND: The aim of the study was to assess whether graduate-entry (GE) medicine is a valid route to medical school in the United Kingdom. We set out to analyze the academic performance of GE students when compared with undergraduate (UG) students by assessing the representation of high achievers and students with fail grades within the two cohorts. METHODS: Using the Freedom of Information Act, we requested examination result data for the academic year 2013-2014 at St. George's Medical School, London, UK. We analyzed the number of students gaining distinction (top 7.5%) and those in the first two deciles. RESULTS: There were 389 GE and 548 UG students in the clinical years. A total of 61.3% of the first or second decile places were awarded to GEs, with 38.7% going to UGs (P < 0.0005). The proportion of GEs achieving the first or second decile was 30.1% compared to 12.8% of UGs (P < 0.01). The proportion of GEs awarded distinction was 12.3% compared to 2.9% of UGs (P < 0.02). The total number of students failing a year at the first attempt was 103. The failure rate within each group was 12.1% for GE and 10.2% for UG. DISCUSSION: Our study found that GE students were overrepresented in the high-achieving groups when compared to UG students. GE students were significantly more likely to be placed in the first or second decile or attain a distinction award. However, GE and UG have a similar failure rate. This study shows that GE programs are a valid entry route to medical courses in the UK.


Assuntos
Desempenho Acadêmico/estatística & dados numéricos , Educação de Graduação em Medicina/métodos , Estudantes de Medicina/estatística & dados numéricos , Educação de Graduação em Medicina/estatística & dados numéricos , Feminino , Humanos , Masculino , Faculdades de Medicina/organização & administração , Reino Unido
14.
Phys Rev Lett ; 117(12): 123002, 2016 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-27689268

RESUMO

We have performed high resolution photoassociation spectroscopy of rubidium ultralong-range Rydberg molecules in the vicinity of the 25P state. Because of the hyperfine interaction in the ground state perturber atom, the emerging mixed singlet-triplet potentials contain contributions from both hyperfine states. We show that this can be used to induce remote spin flips in the perturber atom upon excitation of a Rydberg molecule. Furthermore, when the spin-orbit splitting of the Rydberg state is comparable to the hyperfine splitting in the ground state, the orbital angular momentum of the Rydberg electron is entangled with the nuclear spin of the perturber atom. Our results open new possibilities for the implementation of spin-dependent interactions for ultracold atoms in bulk systems and in optical lattices.

15.
Cell Mol Life Sci ; 72(20): 3931-52, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26153463

RESUMO

The neutral lipids diacylglycerols (DAGs) are involved in a plethora of metabolic pathways. They function as components of cellular membranes, as building blocks for glycero(phospho)lipids, and as lipid second messengers. Considering their central role in multiple metabolic processes and signaling pathways, cellular DAG levels require a tight regulation to ensure a constant and controlled availability. Interestingly, DAG species are versatile in their chemical structure. Besides the different fatty acid species esterified to the glycerol backbone, DAGs can occur in three different stereo/regioisoforms, each with unique biological properties. Recent scientific advances have revealed that DAG metabolizing enzymes generate and distinguish different DAG isoforms, and that only one DAG isoform holds signaling properties. Herein, we review the current knowledge of DAG stereochemistry and their impact on cellular metabolism and signaling. Further, we describe intracellular DAG turnover and its stereochemistry in a 3-pool model to illustrate the spatial and stereochemical separation and hereby the diversity of cellular DAG metabolism.


Assuntos
Diglicerídeos/fisiologia , Transdução de Sinais , Animais , Membrana Celular/metabolismo , Diglicerídeos/química , Diglicerídeos/metabolismo , Insulina/metabolismo , Redes e Vias Metabólicas , Camundongos , Modelos Biológicos , Estereoisomerismo , Fosfolipases Tipo C/metabolismo
16.
Phys Rev Lett ; 115(1): 013003, 2015 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-26182095

RESUMO

We have studied the associative ionization of a Rydberg atom and a ground-state atom in an ultracold Rydberg gas. The measured scattering cross section is 3 orders of magnitude larger than the geometrical size of the produced molecule. This giant enhancement of the reaction kinetics is due to an efficient directed mass transport which is accelerated by the Rydberg electron. We also find that the total inelastic scattering cross section is given by the geometrical size of the Rydberg electron's wave function.

17.
Orthopadie (Heidelb) ; 53(6): 404-414, 2024 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-38739271

RESUMO

BACKGROUND: Muscle injuries are common in football. Imaging diagnostics have a major role in establishing a diagnosis. The main diagnostic procedures are MRI and ultrasound. Both diagnostics have advantages and disadvantages, which should be balanced against each other. NEW ULTRASONIC TECHNIQUES: The role of MRI as the gold standard is increasingly being replaced by high-resolution ultrasound techniques, and MRI imaging is not always useful. To detect complications in the early stages it is advised to perform regular ultrasound-imaging check-ups. The healing process can be monitored, and it offers additional options for ultrasound-guided interventions such as hematoma punctures and targeted infiltrations. ADVANTAGES AND DISADVANTAGES: However, ultrasound imaging is highly user dependent. Experienced operators can eliminate this disadvantage, which makes ultrasound a superior imaging system in many areas, especially for dynamic examinations. Nevertheless, MRI imaging remains a necessary imaging method in certain areas.


Assuntos
Traumatismos em Atletas , Músculo Esquelético , Ultrassonografia , Humanos , Traumatismos em Atletas/diagnóstico por imagem , Traumatismos em Atletas/terapia , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Músculo Esquelético/lesões , Músculo Esquelético/diagnóstico por imagem , Ultrassonografia/métodos
18.
Chem Sci ; 15(7): 2528-2544, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38362440

RESUMO

Amyloid fibrils of proteins such as α-synuclein are a hallmark of neurodegenerative diseases and much research has focused on their kinetics and mechanisms of formation. The question as to the thermodynamic stability of such structures has received much less attention. Here, we newly utilize the principle of transient incomplete separation of species in laminar flow in combination with chemical depolymerization for the quantification of amyloid fibril stability. The relative concentrations of fibrils and monomer at equilibrium are determined through an in situ separation of these species based on their different diffusivity inside a microfluidic capillary. The method is highly sample economical, using much less than a microliter of sample per data point and its only requirement is the presence of aromatic residues (W, Y) because of its label-free nature, which makes it widely applicable. Using this method, we investigate the differences in thermodynamic stability between different fibril polymorphs of α-synuclein and quantify these differences for the first time. Importantly, we show that fibril formation can be under kinetic or thermodynamic control and that a change in solution conditions can both stabilise and destabilise amyloid fibrils. Taken together, our results establish the thermodynamic stability as a well-defined and key parameter that can contribute towards a better understanding of the physiological roles of amyloid fibril polymorphism.

19.
Cancer Discov ; 14(1): 90-103, 2024 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-37861452

RESUMO

The tumor-associated antigen STEAP1 is a potential therapeutic target that is expressed in most prostate tumors and at increased levels in metastatic castration-resistant prostate cancer (mCRPC). We developed a STEAP1-targeted XmAb 2+1 T-cell engager (TCE) molecule, AMG 509 (also designated xaluritamig), that is designed to redirect T cells to kill prostate cancer cells that express STEAP1. AMG 509 mediates potent T cell-dependent cytotoxicity of prostate cancer cell lines in vitro and promotes tumor regression in xenograft and syngeneic mouse models of prostate cancer in vivo. The avidity-driven activity of AMG 509 enables selectivity for tumor cells with high STEAP1 expression compared with normal cells. AMG 509 is the first STEAP1 TCE to advance to clinical testing, and we report a case study of a patient with mCRPC who achieved an objective response on AMG 509 treatment. SIGNIFICANCE: Immunotherapy in prostate cancer has met with limited success due to the immunosuppressive microenvironment and lack of tumor-specific targets. AMG 509 provides a targeted immunotherapy approach to engage a patient's T cells to kill STEAP1-expressing tumor cells and represents a new treatment option for mCRPC and potentially more broadly for prostate cancer. See related commentary by Hage Chehade et al., p. 20. See related article by Kelly et al., p. 76. This article is featured in Selected Articles from This Issue, p. 5.


Assuntos
Anticorpos Biespecíficos , Neoplasias de Próstata Resistentes à Castração , Masculino , Camundongos , Animais , Humanos , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/patologia , Linfócitos T , Imunoterapia , Anticorpos Biespecíficos/uso terapêutico , Microambiente Tumoral , Antígenos de Neoplasias , Oxirredutases/uso terapêutico
20.
Proc Natl Acad Sci U S A ; 107(28): 12605-10, 2010 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-20616015

RESUMO

Epidermal growth factor receptor (EGFR)-specific monoclonal antibodies predominantly inhibit colorectal cancer (CRC) growth by interfering with receptor signaling. Recent analyses have shown that patients with CRC with mutated KRAS and BRAF oncogenes do not profit from treatment with such antibodies. Here we have used the binding domains of cetuximab and pantitumumab for constructing T cell-engaging BiTE antibodies. Both EGFR-specific BiTE antibodies mediated potent redirected lysis of KRAS- and BRAF-mutated CRC lines by human T cells at subpicomolar concentrations. The cetuximab-based BiTE antibody also prevented at very low doses growth of tumors from KRAS- and BRAF-mutated human CRC xenografts, whereas cetuximab was not effective. In nonhuman primates, no significant adverse events were observed during treatment for 3 wk at BiTE serum concentrations inducing, within 1 d, complete lysis of EGFR-overexpressing cancer cells. EGFR-specific BiTE antibodies may have potential to treat CRC that does not respond to conventional antibodies.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Receptores ErbB/antagonistas & inibidores , Anticorpos Monoclonais , Anticorpos Monoclonais Humanizados , Cetuximab , Neoplasias Colorretais/patologia , Receptores ErbB/genética , Receptores ErbB/metabolismo , Genes ras/efeitos dos fármacos , Humanos , Mutação/efeitos dos fármacos , Neoplasias/genética , Proteínas Proto-Oncogênicas B-raf , Fatores de Risco
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