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Alström syndrome (ALMS) is a very rare autosomal-recessive disorder, causing a broad range of clinical defects most notably retinal degeneration, type 2 diabetes, and truncal obesity. The ALMS1 gene encodes a complex and huge â¼0.5 MDa protein, which has hampered analysis in the past. The ALMS1 protein is localized to the centrioles and the basal body of cilia and is involved in signaling processes, for example, TGF-ß signaling. However, the exact molecular function of ALMS1 at the basal body remains elusive and controversial. We recently demonstrated that protein complex analysis utilizing endogenously tagged cells provides an excellent tool to investigate protein interactions of ciliary proteins. Here, CRISPR/Cas9-mediated endogenously tagged ALMS1 cells were used for affinity-based protein complex analysis. Centrosomal and microtubule-associated proteins were identified, which are potential regulators of ALMS1 function, such as the centrosomal protein 70 kDa (CEP70). Candidate proteins were further investigated in ALMS1-deficient hTERT-RPE1 cells. Loss of ALMS1 led to shortened cilia with no change in structural protein localization, for example, acetylated and É£-tubulin, Centrin-3, or the novel interactor CEP70. Conversely, reduction of CEP70 resulted in decreased ALMS1 at the ciliary basal body. Complex analysis of CEP70 revealed domain-specific ALMS1 interaction involving the TPR-containing C-terminal (TRP-CT) fragment of CEP70. In addition to ALMS1, several ciliary proteins, including CEP135, were found to specifically bind to the TPR-CT domain. Data are available via ProteomeXchange with the identifier PXD046401. Protein interactors identified in this study provide candidate lists that help to understand ALMS1 and CEP70 function in cilia-related protein modification, cell death, and disease-related mechanisms.
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Síndrome de Alstrom , Diabetes Mellitus Tipo 2 , Humanos , Síndrome de Alstrom/genética , Síndrome de Alstrom/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Obesidad , Tubulina (Proteína)RESUMEN
Human mutations of the Na+-activated K+ channel Slack (KCNT1) are associated with epilepsy and intellectual disability. Accordingly, Slack knockout mice (Slack-/-) exhibit cognitive flexibility deficits in distinct behavioral tasks. So far, however, the underlying causes as well as the role of Slack in hippocampus-dependent memory functions remain enigmatic. We now report that infant (P6-P14) Slack-/- lack both hippocampal LTD and LTP, likely due to impaired NMDA receptor (NMDAR) signaling. Postsynaptic GluN2B levels are reduced in infant Slack-/-, evidenced by lower amplitudes of NMDAR-meditated excitatory postsynaptic potentials. Low GluN2B affected NMDAR-mediated Ca2+-influx, rendering cultured hippocampal Slack-/-neurons highly insensitive to the GluN2B-specific inhibitor Ro 25-6981. Furthermore, dephosphorylation of the AMPA receptor (AMPAR) subunit GluA1 at S845, which is involved in AMPAR endocytosis during homeostatic and neuromodulator-regulated plasticity, is reduced after chemical LTD (cLTD) in infant Slack-/-. We additionally detect a lack of mGluR-induced LTD in infant Slack-/-, possibly caused by upregulation of the recycling endosome-associated small GTPase Rab4 which might accelerate AMPAR recycling from early endosomes. Interestingly, LTP and mGluR LTD, but not LTD and S845 dephosphorylation after cLTD are restored in adult Slack-/-. This together with normalized expression levels of GluN2B and Rab4 hints to developmental "restoration" of LTP expression despite Slack ablation, whereas in infant and adult brain, NMDAR-dependent LTD induction depends on this channel. Based on the present findings, NMDAR and vesicular transport might represent novel targets for the therapy of intellectual disability associated with Slack mutations. Consequently, careful modulation of hippocampal Slack activity should also improve learning abilities.
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Potenciales de Acción , Hipocampo/fisiología , Potenciación a Largo Plazo , Proteínas del Tejido Nervioso/fisiología , Plasticidad Neuronal , Neuronas/fisiología , Canales de potasio activados por Sodio/fisiología , Sinapsis/fisiología , Animales , Animales Recién Nacidos , Calcio/metabolismo , Potenciales Postsinápticos Excitadores , Depresión Sináptica a Largo Plazo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores de N-Metil-D-Aspartato/genética , Receptores de N-Metil-D-Aspartato/metabolismoRESUMEN
The universally conserved signal recognition particle (SRP) system mediates the targeting of membrane proteins to the translocon in a multistep process controlled by GTP hydrolysis. Here we present the 2.6 Å crystal structure of the GTPase domains of the E. coli SRP protein (Ffh) and its receptor (FtsY) in complex with the tetraloop and the distal region of SRP-RNA, trapped in the activated state in presence of GDP:AlF4. The structure reveals the atomic details of FtsY recruitment and, together with biochemical experiments, pinpoints G83 as the key RNA residue that stimulates GTP hydrolysis. Insertion of G83 into the FtsY active site orients a single glutamate residue provided by Ffh (E277), triggering GTP hydrolysis and complex disassembly at the end of the targeting cycle. The complete conservation of the key residues of the SRP-RNA and the SRP protein implies that the suggested chemical mechanism of GTPase activation is applicable across all kingdoms.
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Proteínas Bacterianas/genética , GTP Fosfohidrolasas/genética , GTP Fosfohidrolasas/metabolismo , ARN/genética , Receptores Citoplasmáticos y Nucleares/genética , Partícula de Reconocimiento de Señal/genética , Partícula de Reconocimiento de Señal/metabolismo , Compuestos de Aluminio/farmacología , Proteínas Bacterianas/metabolismo , Secuencia de Bases , Dominio Catalítico/efectos de los fármacos , Dominio Catalítico/genética , Escherichia coli/enzimología , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Fluoruros/farmacología , Activadores de GTP Fosfohidrolasa/farmacología , Guanosina Difosfato/genética , Guanosina Difosfato/metabolismo , Hidrólisis/efectos de los fármacos , Datos de Secuencia Molecular , ARN/metabolismo , ARN Bacteriano/genética , ARN Bacteriano/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Análisis de Secuencia de ADNRESUMEN
OBJECTIVES: Video consultations are becoming more and more important for health care providers as they enable new treatment options. Since 2017 video consultations have been used by the public health insurance companies in Germany. However, similar options are lacking in the employer's liability insurance association (BG in Germany) health insurance system. The aim of this article is to present and discuss possible applications of video consultations in the latter system and to evaluate economic advantages. METHODS: Possible applications of video consultations are discussed in the context of feasibility, potential benefits and the existing scale of fees for physicians (in Germany UV-GOÄ). RESULTS: Video consultations can be used for follow-up evaluations as well as preparation for initial medical examinations especially in complex cases and for case conferences. Even though video consultations are not included in the reimbursement system, similar CPT codes (current procedural terminology) already do exist. CONCLUSIONS: Video consultations might help improve the quality and reduce the costs of the public health insurance system. Furthermore, since video consultations can be expected to become more important in the future, they should be included as a standard tool in the employer's liability insurance association insurance system and an adequate reimbursement system be established.
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Seguro por Accidentes , Telemedicina , Análisis Costo-Beneficio , Alemania , Derivación y ConsultaRESUMEN
BACKGROUND: Discoveries in cellular dynamics and tissue development constantly reshape our understanding of fundamental biological processes such as embryogenesis, wound-healing, and tumorigenesis. High-quality microscopy data and ever-improving understanding of single-cell effects rapidly accelerate new discoveries. Still, many computational models either describe few cells highly detailed or larger cell ensembles and tissues more coarsely. Here, we connect these two scales in a joint theoretical model. RESULTS: We developed a highly parallel version of the cellular Potts model that can be flexibly applied and provides an agent-based model driving cellular events. The model can be modular extended to a multi-model simulation on both scales. Based on the NAStJA framework, a scaling implementation running efficiently on high-performance computing systems was realized. We demonstrate independence of bias in our approach as well as excellent scaling behavior. CONCLUSIONS: Our model scales approximately linear beyond 10,000 cores and thus enables the simulation of large-scale three-dimensional tissues only confined by available computational resources. The strict modular design allows arbitrary models to be configured flexibly and enables applications in a wide range of research questions. Cells in Silico (CiS) can be easily molded to different model assumptions and help push computational scientists to expand their simulations to a new area in tissue simulations. As an example we highlight a 10003 voxel-sized cancerous tissue simulation at sub-cellular resolution.
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Células/metabolismo , Simulación por Computador , Especificidad de Órganos , Transporte Biológico , Muerte Celular , Difusión , Modelos Teóricos , Mutación/genética , Interfaz Usuario-ComputadorRESUMEN
Mitochondrial ribosomes synthesize a number of highly hydrophobic proteins encoded on the genome of mitochondria, the organelles in eukaryotic cells that are responsible for energy conversion by oxidative phosphorylation. The ribosomes in mammalian mitochondria have undergone massive structural changes throughout their evolution, including ribosomal RNA shortening and acquisition of mitochondria-specific ribosomal proteins. Here we present the three-dimensional structure of the 39S large subunit of the porcine mitochondrial ribosome determined by cryo-electron microscopy at 4.9 Å resolution. The structure, combined with data from chemical crosslinking and mass spectrometry experiments, reveals the unique features of the 39S subunit at near-atomic resolution and provides detailed insight into the architecture of the polypeptide exit site. This region of the mitochondrial ribosome has been considerably remodelled compared to its bacterial counterpart, providing a specialized platform for the synthesis and membrane insertion of the highly hydrophobic protein components of the respiratory chain.
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Mitocondrias/química , Subunidades Ribosómicas/química , Animales , Bovinos , Microscopía por Crioelectrón , Interacciones Hidrofóbicas e Hidrofílicas , Espectrometría de Masas , Mitocondrias/ultraestructura , Proteínas Mitocondriales/química , Proteínas Mitocondriales/ultraestructura , Modelos Moleculares , Conformación de Ácido Nucleico , Conformación Proteica , ARN Ribosómico 16S/química , ARN Ribosómico 16S/ultraestructura , Proteínas Ribosómicas/química , Proteínas Ribosómicas/ultraestructura , Subunidades Ribosómicas/ultraestructura , PorcinosRESUMEN
BACKGROUND: Fractional flow reserve (FFR) guided percutaneous coronary intervention (PCI) has been validated in patients with stable coronary artery disease (CAD) but has not yet been verified under specific conditions such as heart failure or microvascular dysfunction. The aim of the present study was to examine the influence of specific patient comorbidities on FFR values and thus the frequency of PCI in patients with intermediate coronary stenosis. METHODS: A total of 652 patients with CAD and intermediate coronary stenosis who were assessed for FFR were included in this retrospective study. In a subgroup analysis, specific comorbidities such as heart failure with non-ST-segment-elevated acute coronary syndrome (NSTE-ACS), heart failure, diabetes mellitus, atrial fibrillation (AF), and left ventricular hypertrophy (LVH) were considered. RESULTS: In all lesions with an FFRâ¯≤ 0.80 (nâ¯= 227/808, 28.1%), PCI was performed using drug-eluting stents. Pathological FFR values (FFRâ¯≤ 0.80) before PCI were most frequently observed in the left anterior descending artery (LAD; nâ¯= 168/418, 39.9%) followed by the right coronary artery (RCA; nâ¯= 37/178, 20.7%) and the left circumflex artery (LCX; 22/223, 9.8%). The comorbidities NSTE-ACS (pâ¯= 0.28), heart failure with reduced ejection fraction (HFrEF; pâ¯= 0.63), heart failure with preserved ejection fraction (HFpEF; pâ¯= 0.3719), diabetes mellitus (pâ¯= 0.177), or LVH (pâ¯= 0.407) had no major impact on the occurrence of pathological FFR values; there was also no association between FFR and the occurrence of lesions in the different target vessels. CONCLUSION: The occurrence of pathological FFR values, most frequently documented in the LAD, was the same in patients with or without HFrEF, HFpEF, diabetes mellitus, AF, and LVH, demonstrating that these comorbidities did not influence FFR values and, thus, the indication for PCI.
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Enfermedad de la Arteria Coronaria , Estenosis Coronaria , Reserva del Flujo Fraccional Miocárdico , Insuficiencia Cardíaca , Intervención Coronaria Percutánea , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/epidemiología , Enfermedad de la Arteria Coronaria/cirugía , Estenosis Coronaria/diagnóstico por imagen , Estenosis Coronaria/epidemiología , Estenosis Coronaria/cirugía , Insuficiencia Cardíaca/epidemiología , Humanos , Estudios Retrospectivos , Volumen Sistólico , Resultado del TratamientoRESUMEN
Aqueous proton transport plays a key role in acid-base neutralization and energy transport through biological membranes and hydrogen fuel cells. Extensive experimental and theoretical studies have resulted in a highly detailed elucidation of one of the underlying microscopic mechanisms for aqueous excess proton transport, known as the von Grotthuss mechanism, involving different hydrated proton configurations with associated high fluxional structural dynamics. Hydroxide transport, with approximately 2-fold-lower bulk diffusion rates compared to those of excess protons, has received much less attention. We present femtosecond UV/IR pump-probe experiments and ab initio molecular dynamics simulations of different proton transport pathways of bifunctional photoacid 7-hydroxyquinoline (7HQ) in water/methanol mixtures. For 7HQ solvent-dependent photoacidity, free-energy-reactivity correlation behavior and quantum mechanics/molecular mechanics (QM/MM) trajectories point to a dominant OH-/CH3O- transport pathway for all water/methanol mixing ratios investigated. Our joint ultrafast infrared spectroscopic and ab initio molecular dynamics study provides conclusive evidence for the hydrolysis/methanolysis acid-base neutralization pathway, as formulated by Manfred Eigen half a century ago. Our findings on the distinctly different acid-base reactivities for aromatic hydroxyl and aromatic nitrogen functionalities suggest the usefulness of further exploration of these free-energy-reactivity correlations as a function of solvent polarity. Ultimately the determination of solvent-dependent acidities will contribute to a better understanding of proton-transport mechanisms at weakly polar surfaces and near polar or ionic regions in transmembrane proton pump proteins or hydrogen fuel cell materials.
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A quantum-chemistry based protocol, termed MOSS-DFT, is presented for the prediction of 13C and 1H NMR chemical shifts of a wide range of organic molecules in aqueous solution, including metabolites. Molecular motif-specific linear scaling parameters are reported for five different density functional theory (DFT) methods (B97-2/pcS-1, B97-2/pcS-2, B97-2/pcS-3, B3LYP/pcS-2, and BLYP/pcS-2), which were applied to a large set of 176 metabolite molecules. The chemical shift root-mean-square deviations (RMSD) for the best method, B97-2/pcS-3, are 1.93 and 0.154 ppm for 13C and 1H chemical shifts, respectively. Excellent results have been obtained for chemical shifts of methyl and aromatic 13C and 1H that are not directly bonded to a heteroatom (O, N, S, or P) with RMSD values of 1.15/0.079 and 1.31/0.118 ppm, respectively. This study not only demonstrates how NMR chemical shift in aqueous environment can be improved over the commonly used global linear scaling approach, but also allows for motif-specific error estimates, which are useful for an improved chemical shift-based verification of metabolite candidates of metabolomics samples containing unknown components.
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Eukaryotic ribosomes are significantly larger and more complex than their prokaryotic counterparts. This parallels the increased complexity of the associated cellular machinery responsible for translation initiation, ribosome assembly, and the regulation of protein synthesis in eukaryotic cells. The recently determined crystal structures of the small (40S) and large (60S) ribosomal subunits and the 80S ribosome now provide an atomic description of this essential molecular machine and reveal its eukaryote-specific features. In this review, we discuss the common structural principles underlying the evolution of both ribosomal subunits. The recently obtained structural information provides a framework for further genetic, biochemical and structural studies of eukaryotic ribosomes. At the same time, it facilitates a direct comparison between prokaryotic and eukaryotic ribosomal features.
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Biosíntesis de Proteínas , ARN Ribosómico/química , Proteínas Ribosómicas/química , Ribosomas/química , Cristalografía por Rayos X , Células Eucariotas/metabolismo , Modelos Moleculares , ARN Ribosómico/metabolismo , Ribonucleoproteínas/química , Ribonucleoproteínas/metabolismo , Proteínas Ribosómicas/metabolismo , Ribosomas/metabolismoRESUMEN
The photophysics of 7-hydroxyquinoline (7HQ) in protic media results from an interplay of acid-base chemistry, prompted by the effects of photoacidity of the hydroxyl group and photobasicity of the nitrogen atom in the quinoline aromatic system. With ultrafast IR spectroscopic measurements, we follow the proton transfer dynamics of 7HQ in its four possible charged forms in methanol solution. Using deuterated methanol as solvent, we determine deuteron transfer rates from the neutral to the zwitterionic form to be 330 ps, those from the cationic form to the zwitterionic form to be 170 ps, and those from the anionic form to the zwitterionic form to be 600 ps. We compare the observed IR-active fingerprint marker patterns in the electronic ground state and the first electronically excited 1Lb-state with those calculated using density functional theory and time-dependent density functional theory, respectively, and find good correspondence between experimental and calculated transitions. The calculations provide insight into the nature of electronic excitation of these four different charged forms of 7HQ, suggesting the key role of electronic charge distribution changes upon electronic excitation of 7HQ and hydrogen bond changes at the donor hydroxyl and acceptor nitrogen moieties.
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We elucidate the characteristic proton pathways and the transient infrared signatures of intermediate complexes during the first picoseconds of photoinduced protonation dynamics of a photoacid (N-methyl-6-hydroxyquinolinium) in aqueous solution from first-principles molecular dynamics simulations. Our results indicate that the typical latency time between photoexcitation and proton dissociation ranges from 1 ps to longer time time scales (â¼100 ps). The rate-limiting step for the actual dissociation of the proton into the solvent is the solvation structure of the first accepting water molecule. The nature of the proton pathway in water (stepwise or concerted) is not unique but determined by the coordination number of the accepting water molecules along the hydrogen bond chain. We find a characteristic uncommon infrared mode at â¼1300 cm(-1) of the transient photobase-Eigen cation complex immediately after photodissociation that we predict to be observable experimentally in time-resolved IR spectroscopy. A broad continuous absorption band from 1500 to 2000 cm(-1) arises from the acidic proton imminently before dissociation.
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Ácidos/química , Protones , Espectrofotometría Infrarroja/métodos , Simulación de Dinámica Molecular , SolubilidadRESUMEN
We introduce a database (HAB11) of electronic coupling matrix elements (H(ab)) for electron transfer in 11 π-conjugated organic homo-dimer cations. High-level ab inito calculations at the multireference configuration interaction MRCI+Q level of theory, n-electron valence state perturbation theory NEVPT2, and (spin-component scaled) approximate coupled cluster model (SCS)-CC2 are reported for this database to assess the performance of three DFT methods of decreasing computational cost, including constrained density functional theory (CDFT), fragment-orbital DFT (FODFT), and self-consistent charge density functional tight-binding (FODFTB). We find that the CDFT approach in combination with a modified PBE functional containing 50% Hartree-Fock exchange gives best results for absolute H(ab) values (mean relative unsigned error = 5.3%) and exponential distance decay constants ß (4.3%). CDFT in combination with pure PBE overestimates couplings by 38.7% due to a too diffuse excess charge distribution, whereas the economic FODFT and highly cost-effective FODFTB methods underestimate couplings by 37.6% and 42.4%, respectively, due to neglect of interaction between donor and acceptor. The errors are systematic, however, and can be significantly reduced by applying a uniform scaling factor for each method. Applications to dimers outside the database, specifically rotated thiophene dimers and larger acenes up to pentacene, suggests that the same scaling procedure significantly improves the FODFT and FODFTB results for larger π-conjugated systems relevant to organic semiconductors and DNA.
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The AUD2IT-algorithm is a tool to structure the data, which is collected during an emergency treatment. The goal is on the one hand to structure the documentation of the data and on the other hand to give a standardised data structure for the report during handover of an emergency patient. AUD2IT-algorithm was developed to provide residents a documentation aid, which helps to structure the medical reports without getting lost in unimportant details or forgetting important information. The sequence of anamnesis, clinical examination, considering a differential diagnosis, technical diagnostics, interpretation and therapy is rather an academic classification than a description of the real workflow. In a real setting, most of these steps take place simultaneously. Therefore, the application of the AUD2IT-algorithm should also be carried out according to the real processes. A big advantage of the AUD2IT-algorithm is that it can be used as a structure for the entire treatment process and also is entirely usable as a handover protocol within this process to make sure, that the existing state of knowledge is ensured at each point of a team-timeout. PR-E-(AUD2IT)-algorithm makes it possible to document a treatment process that, in principle, does not have to be limited to the field of emergency medicine. Also, in the outpatient treatment the PR-E-(AUD2IT)-algorithm could be used and further developed. One example could be the preparation and allocation of needed resources at the general practitioner. The algorithm is a standardised tool that can be used by healthcare professionals of any level of training. It gives the user a sense of security in their daily work.
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BACKGROUND: During the SARS-CoV2 pandemic, the TeleCOVID application was developed in Hessen to connect the intensive care units via telemedicine. After successful implementation, the application should be extended to other indication areas in intensive care medicine. OBJECTIVES: The purpose of this study was to evaluate other indications for which the application can be used and which technical requirements are associated with this. MATERIALS AND METHODS: To answer these questions, guideline-based expert interviews were conducted, which were evaluated using a qualitative content analysis. RESULTS: The survey showed that TeleCOVID can be extended to other indication areas in intensive care. Numerous technical requirements were formulated that should be specifically considered when the application is further developed. CONCLUSIONS: The telemedical networking of intensive care units generates added value for the actors involved. However, it is important that the data is collected in the best possible standardized and structured way. The communication process should be automated wherever possible to minimise the workload for the participating persons.
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The management of medial meniscus horizontal cleavage tears can be challenging. Currently, several treatment options, including nonoperative and surgical options, have been proposed in the literature. Different repair techniques aiming to promote the healing process have been reported and have shown good outcomes. However, recurrent parameniscal cysts and decreased meniscal volume have also been reported. In this Technical Note, a novel surgical technique to repair a horizontal cleavage tear of the posterior horn of the medial meniscus is reported in young patients. The technique uses a strip of autologous quadriceps tendon to fill the void between the upper and lower meniscal leaflets followed by an all-inside compression suture. Both of these technical features aim to overcome the limitations of current repair techniques.
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Purpose: This original case series aims to describe an uncommon triad of clinical signs in patients presenting with persistent pain and inability to resume physical activities after knee hyperextension trauma. Methods: Patient history, clinical examination, arthroscopic findings and investigations of 12 patients who consulted with the senior author are presented. Results: Twelve patients (seven males/five females) presented with persistent pain after knee hyperextension trauma either in sport or a traffic accident. They had a median age of 18.5 and a median body mass index of 23 kg/m2. All had medical visits and at least one magnetic resonance imaging (MRI) before visiting the senior author's institution but the cause of their problems could not be explained. The clinical examination of the injured knee appeared normal except for an uncommon triad of clinical signs with the knee close to extension: (1) a grade 1+ anterior-posterior laxity around 10-20° of knee flexion with a firm end-point (pseudo-Lachman sign), (2) a grade 1+ tibiofemoral step-off sign with a posterior drawer at 10-20° of knee flexion and (3) an increased knee hyperextension compared to the contralateral side. Arthroscopy of eight patients confirmed the pseudo-Lachman sign with a grade I posterior drawer close to knee extension, normal posterior laxity at 90° of knee flexion and an intact anterior cruciate ligament. Conclusion: Patients displayed an increased hyperextension and posterior laxity close to knee extension which normalised at 90° of knee flexion. In patients with a history of knee hyperextension trauma associated with persistent pain, inability to resume physical activities, inconclusive MRIs and a standard clinical examination, clinicians should consider extending their investigations with the knee close to extension to identify this clinical triad consistent with a lesion to the posteromedial bundle of the posterior cruciate ligament. Level of evidence: Level IV.
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Crumbs homolog 1 (CRB1) is one of the key genes linked to retinitis pigmentosa and Leber congenital amaurosis, which are characterized by a high clinical heterogeneity. The Crumbs family member CRB2 has a similar protein structure to CRB1, and in zebrafish, Crb2 has been shown to interact through the extracellular domain. Here, we show that CRB1 and CRB2 co-localize in the human retina and human iPSC-derived retinal organoids. In retina-specific pull-downs, CRB1 was enriched in CRB2 samples, supporting a CRB1-CRB2 interaction. Furthermore, novel interactors of the crumbs complex were identified, representing a retina-derived protein interaction network. Using co-immunoprecipitation, we further demonstrate that human canonical CRB1 interacts with CRB1 and CRB2, but not with CRB3, which lacks an extracellular domain. Next, we explored how missense mutations in the extracellular domain affect CRB1-CRB2 interactions. We observed no or a mild loss of CRB1-CRB2 interaction, when interrogating various CRB1 or CRB2 missense mutants in vitro. Taken together, our results show a stable interaction of human canonical CRB2 and CRB1 in the retina.
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Amaurosis Congénita de Leber , Retinitis Pigmentosa , Animales , Humanos , Pez Cebra/genética , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Retina/metabolismo , Retinitis Pigmentosa/genética , Retinitis Pigmentosa/metabolismo , Amaurosis Congénita de Leber/genética , Amaurosis Congénita de Leber/metabolismo , Proteínas del Ojo/genética , Proteínas del Ojo/metabolismo , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Proteínas Portadoras/metabolismoRESUMEN
Due to the proliferation-induced high demand of cancer cells for folic acid (FA), significant overexpression of folate receptors 1 (FR1) is detected in most cancers. To our knowledge, a detailed characterization of FR1 expression and regulation regarding therapeutic and diagnostic feasibilities in prostate cancer (PCa) has not been described. In the present study, cell cultures, as well as tissue sections, were analyzed using Western blot, qRT-PCR and immunofluorescence. In addition, we utilized FA-functionalized lipoplexes to characterize the potential of FR1-targeted delivery into PCa cells. Interestingly, we detected a high level of FR1-mRNA in healthy prostate epithelial cells and healthy prostate tissue. However, we were able to show that PCa cells in vitro and PCa tissue showed a massively enhanced FR1 membrane localization where the receptor can finally gain its function. We were able to link these changes to the overexpression of GPI-transamidase (GPI-T) by image analysis. PCa cells in vitro and PCa tissue show the strongest overexpression of GPI-T and thereby induce FR1 membrane localization. Finally, we utilized FA-functionalized lipoplexes to selectively transfer pDNA into PCa cells and demonstrate the therapeutic potential of FR1. Thus, FR1 represents a very promising candidate for targeted therapeutic transfer pathways in PCa and in combination with GPI-T, may provide predictive imaging in addition to established diagnostics.
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BACKGROUND: Older patients presenting to the emergency department (ED) after falling are increasingly prevalent. Falls are associated with functional decline and death. Biomarkers predicting short-term mortality might facilitate decisions regarding resource allocation and disposition. D-dimer levels are used to rule out thromboembolic disease, while copeptin and adrenomedullin (MR-proADM) may be used as measures of the patient`s stress level. These nonspecific biomarkers were selected as potential predictors for mortality. METHODS: Prospective, international, multicenter, cross-sectional observation was performed in two tertiary and two regional hospitals in Germany and Switzerland. Patients aged 65 years or older presenting to the ED after a fall were enrolled. Demographic data, Activities of Daily Living (ADL), and D-dimers were collected upon presentation. Copeptin and MR-proADM levels were determined from frozen samples. Primary outcome was 30-day mortality; and secondary outcomes were mortality at 90, 180, and 365 days. RESULTS: Five hundred and seventy-two patients were included. Median age was 83 [IQR 78, 89] years, 236 (67.7%) were female. Mortality overall was 3.1% (30 d), 5.4% (90 d), 7.5% (180 d), and 13.8% (365 d), respectively. Non-survivors were older, had a lower ADL index and higher levels of all three biomarkers. Elevated levels of MR-proADM and D-dimer were associated with higher risk of mortality. MR-proADM and D-dimer showed high sensitivity and low negative likelihood ratio regarding short-term mortality, whereas copeptin did not. CONCLUSION: D-dimer and MR-proADM levels might be useful as prognostic markers in older patients presenting to the ED after a fall, by identifying patients at low risk of short-term mortality. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02244983.