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1.
PLoS Biol ; 20(2): e3001427, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35192607

RESUMEN

The 2 major molecular switches in biology, kinases and GTPases, are both contained in the Parkinson disease-related leucine-rich repeat kinase 2 (LRRK2). Using hydrogen-deuterium exchange mass spectrometry (HDX-MS) and molecular dynamics (MD) simulations, we generated a comprehensive dynamic allosteric portrait of the C-terminal domains of LRRK2 (LRRK2RCKW). We identified 2 helices that shield the kinase domain and regulate LRRK2 conformation and function. One helix in COR-B (COR-B Helix) tethers the COR-B domain to the αC helix of the kinase domain and faces its activation loop, while the C-terminal helix (Ct-Helix) extends from the WD40 domain and interacts with both kinase lobes. The Ct-Helix and the N-terminus of the COR-B Helix create a "cap" that regulates the N-lobe of the kinase domain. Our analyses reveal allosteric sites for pharmacological intervention and confirm the kinase domain as the central hub for conformational control.


Asunto(s)
Dominio Catalítico , Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina/química , Simulación de Dinámica Molecular , Conformación Proteica , Regulación Alostérica , Sitio Alostérico , Medición de Intercambio de Deuterio/métodos , Humanos , Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina/genética , Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina/metabolismo , Espectrometría de Masas/métodos , Mutación , Unión Proteica
2.
Proc Natl Acad Sci U S A ; 119(9)2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35217606

RESUMEN

Mutations in the gene coding for leucine-rich repeat kinase 2 (LRRK2) are a leading cause of the inherited form of Parkinson's disease (PD), while LRRK2 overactivation is also associated with the more common idiopathic form of PD. LRRK2 is a large multidomain protein, including a GTPase as well as a Ser/Thr protein kinase domain. Common, disease-causing mutations increase LRRK2 kinase activity, presenting LRRK2 as an attractive target for drug discovery. Currently, drug development has mainly focused on ATP-competitive kinase inhibitors. Here, we report the identification and characterization of a variety of nanobodies that bind to different LRRK2 domains and inhibit or activate LRRK2 in cells and in in vitro. Importantly, nanobodies were identified that inhibit LRRK2 kinase activity while binding to a site that is topographically distinct from the active site and thus act through an allosteric inhibitory mechanism that does not involve binding to the ATP pocket or even to the kinase domain. Moreover, while certain nanobodies completely inhibit the LRRK2 kinase activity, we also identified nanobodies that specifically inhibit the phosphorylation of Rab protein substrates. Finally, in contrast to current type I kinase inhibitors, the studied kinase-inhibitory nanobodies did not induce LRRK2 microtubule association. These comprehensively characterized nanobodies represent versatile tools to study the LRRK2 function and mechanism and can pave the way toward novel diagnostic and therapeutic strategies for PD.


Asunto(s)
Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina/metabolismo , Enfermedad de Parkinson/metabolismo , Anticuerpos de Dominio Único , Adenosina Trifosfato/metabolismo , Regulación Alostérica , Animales , Sitios de Unión , Mapeo Epitopo , Células HEK293 , Humanos , Ratones , Microtúbulos/metabolismo , Fosforilación , Unión Proteica , Células RAW 264.7 , Proteínas de Unión al GTP rab/metabolismo
3.
Proc Natl Acad Sci U S A ; 118(23)2021 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-34088839

RESUMEN

To explore how pathogenic mutations of the multidomain leucine-rich repeat kinase 2 (LRRK2) hijack its finely tuned activation process and drive Parkinson's disease (PD), we used a multitiered approach. Most mutations mimic Rab-mediated activation by "unleashing" kinase activity, and many, like the kinase inhibitor MLi-2, trap LRRK2 onto microtubules. Here we mimic activation by simply deleting the inhibitory N-terminal domains and then characterize conformational changes induced by MLi-2 and PD mutations. After confirming that LRRK2RCKW retains full kinase activity, we used hydrogen-deuterium exchange mass spectrometry to capture breathing dynamics in the presence and absence of MLi-2. Solvent-accessible regions throughout the entire protein are reduced by MLi-2 binding. With molecular dynamics simulations, we created a dynamic portrait of LRRK2RCKW and demonstrate the consequences of kinase domain mutations. Although all domains contribute to regulating kinase activity, the kinase domain, driven by the DYGψ motif, is the allosteric hub that drives LRRK2 regulation.


Asunto(s)
Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina/química , Simulación de Dinámica Molecular , Secuencias de Aminoácidos , Humanos , Espectrometría de Masas de Intercambio de Hidrógeno-Deuterio , Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina/genética , Dominios Proteicos , Transporte de Proteínas
4.
Sensors (Basel) ; 24(8)2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38676045

RESUMEN

Among other methods, UWB-based multi-anchor localization systems have been established for industrial indoor localization systems. However, multi-anchor systems have high costs and installation effort. By exploiting the multipath propagation of the UWB signal, the infrastructure and thus the costs of conventional systems can be reduced. Our UWB Single-Anchor Localization System (SALOS) successfully pursues this approach. The idea is to create a localization system with sophisticated signal modeling. Therefore, measured reference, like fingerprinting or training, is not required for position estimation. Although SALOS has already been implemented and tested successfully in an outdoor scenario with multipath propagation, it has not yet been evaluated in an indoor environment with challenging and hardly predictable multipath propagation. For this purpose, we have developed new algorithms for the existing hardware, mainly a three-dimensional statistical multipath propagation model for arbitrary spatial geometries. The signal propagation between the anchor and predefined candidate points for the tag position is modeled in path length and complex-valued receive amplitudes. For position estimation, these modeled signals are combined to multiple sets and compared to UWB measurements via a similarity metric. Finally, a majority decision of multiple position estimates is performed. For evaluation, we implement our localization system in a modular fashion and install the system in a building. For a fixed grid of 20 positions, the localization is evaluated in terms of position accuracy. The system results in correct position estimations for more than 73% of the measurements.

5.
Eur Spine J ; 32(10): 3370-3378, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37584698

RESUMEN

PURPOSE: To outline clinical effectiveness of continuous epidural analgesia (CEA) in patients with failed back surgery syndrome (FBSS) or lumbar spinal stenosis (LSS) depending on severity of spinal degeneration. METHODS: In this retrospective cohort study, all patients with FBSS or LSS who underwent CEA within an inpatient rehabilitation program were evaluated. The pain reduction was measured by VAS on an hourly basis. Substantial pain reduction was defined as a minimal clinically important difference (MCID) > 50%. Severity of spinal degeneration, side effects and patient-specific characteristics were documented. RESULT: We included a total of 148 patients with 105 patients suffering from FBSS and 48 with LSS. The average pain reduction was - 37.6 ± 19.2 in FBSS and - 38.1 ± 17.8 in LSS group (p < .001 and p < .001, respectively). In the FBSS group, sensory deficits (p = .047) and numbness (p = .002), and in the LSS group, a severe disability measured by ODI (38.2 ± 15.4 vs. 57.3 ± 11.3, p < .001) significantly contributed to a worse outcome. The severity of the spinal degeneration and psychological disorders did not affect the pain reduction in terms of MCID. CONCLUSIONS: This study provides new evidence about CEA in the treatment of FBSS and LSS. CEA provides a significant pain reduction even under intensified physiotherapeutic exercising in patients with severe spinal degeneration and a broad variety of secondary diagnoses. Neurologic deficits in case of FBSS and severe disability in case of LSS may be risk factors for less favorable outcome.


Asunto(s)
Analgesia Epidural , Síndrome de Fracaso de la Cirugía Espinal Lumbar , Estenosis Espinal , Humanos , Estudios Retrospectivos , Estenosis Espinal/complicaciones , Estenosis Espinal/cirugía , Estenosis Espinal/diagnóstico , Resultado del Tratamiento , Vértebras Lumbares/cirugía
6.
Sensors (Basel) ; 23(4)2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36850796

RESUMEN

Device-free localization (DFL) systems exploit changes in the radio frequency channel by measuring, for example, the channel impulse response (CIR), to detect and localize obstacles within a target area. However, due to a lack of well-defined interfaces, missing modularization, as well as complex system configuration, it is difficult to deploy DFL systems outside of laboratory setups. This paper focused on the system view and the challenges that come with setting up a DFL system in an indoor environment. We propose MA-RTI, a modular DFL system that is easy to set up, and which utilizes a multipath-assisted (MA) radio-tomographic imaging (RTI) algorithm. To achieve a modular DFL system, we proposed and implemented an architectural model for DFL systems. For minimizing the configuration overhead, we applied a 3D spatial model, that helps in placing the sensors and calculating the required calibration parameters. Therefore, we configured the system solely with idle measurements and a 3D spatial model. We deployed such a DFL system and evaluated it in a real-world office environment with four sensor nodes. The radio technology was ultra-wideband (UWB) and the corresponding signal measurements were CIRs. The DFL system operated with CIRs that provided a sub-nanosecond time-domain resolution. After pre-processing, the update rate was approximately 46 Hz and it provided a localization accuracy of 1.0 m in 50% of all cases and 1.8 m in 80% of all cases. MA fingerprinting approaches lead to higher localization accuracy, but require a labor-intensive training phase.

7.
Ann Surg ; 275(6): 1130-1136, 2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33055589

RESUMEN

OBJECTIVE: To assess the impact of surgical technique in regard to morbidity and mortality after neoadjuvant treatment for esophageal cancer. BACKGROUND: The SAKK trial 75/08 was a multicenter phase III trial (NCT01107639) comparing induction chemotherapy followed by chemoradiation and surgery in patients with locally advanced esophageal cancer. METHODS: Patients in the control arm received induction chemotherapy with cisplatin and docetaxel, followed by concomitant chemoradiation therapy with cisplatin, docetaxel, and 45Gy. In the experimental arm, the same regimen was used with addition of cetuximab. After completion of neoadjuvant treatment, patients underwent esophagectomy. The experimental arm received adjuvant cetuximab. Surgical outcomes and complications were prospectively recorded and analyzed. RESULTS: Total of 259 patients underwent esophagectomy. Overall complication rate was 56% and reoperation rate was 15% with no difference in complication rates for transthoracic versus transhiatal resections (56% vs 54%, P = 0.77), nor for video assisted thoracic surgeries (VATS) versus open transthoracic resections (67% vs 55%, P = 0.32). There was a trend to higher overall complication rates in squamous cell carcinoma versus adenocarcinoma (65% vs 51%, P = 0.035), and a significant difference in ARDS in squamous cell carcinoma with 14% versus 2% in adenocarcinoma (P = 0.0002). For patients with involved lymph nodes, a lymph node ratio of ≥0.1 was an independent predictor of PFS (HR 2.5, P = 0.01) and OS (HR 2.2, P = 0.03). CONCLUSIONS: This trial showed no difference in surgical complication rates between transthoracic and transhiatal resections. For patients with involved lymph nodes, lymph node ratio was an independent predictor of progression free survival and overall survival.


Asunto(s)
Adenocarcinoma , Carcinoma de Células Escamosas , Neoplasias Esofágicas , Adenocarcinoma/patología , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/terapia , Cetuximab/uso terapéutico , Cisplatino/uso terapéutico , Docetaxel/uso terapéutico , Esofagectomía/métodos , Humanos , Terapia Neoadyuvante/métodos , Estadificación de Neoplasias , Tasa de Supervivencia , Resultado del Tratamiento
8.
Proc Natl Acad Sci U S A ; 116(30): 14979-14988, 2019 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-31292254

RESUMEN

Leucine-rich repeat kinase 2 (LRRK2) is a large multidomain protein, and LRRK2 mutants are recognized risk factors for Parkinson's disease (PD). Although the precise mechanisms that control LRRK2 regulation and function are unclear, the importance of the kinase domain is strongly implicated, since 2 of the 5 most common familial LRRK2 mutations (G2019S and I2020T) are localized to the conserved DFGψ motif in the kinase core, and kinase inhibitors are under development. Combining the concept of regulatory (R) and catalytic (C) spines with kinetic and cell-based assays, we discovered a major regulatory mechanism embedded within the kinase domain and show that the DFG motif serves as a conformational switch that drives LRRK2 activation. LRRK2 is quite unusual in that the highly conserved Phe in the DFGψ motif, which is 1 of the 4 R-spine residues, is replaced with tyrosine (DY2018GI). A Y2018F mutation creates a hyperactive phenotype similar to the familial mutation G2019S. The hydroxyl moiety of Y2018 thus serves as a "brake" that stabilizes an inactive conformation; simply removing it destroys a key hydrogen-bonding node. Y2018F, like the pathogenic mutant I2020T, spontaneously forms LRRK2-decorated microtubules in cells, while the wild type and G2019S require kinase inhibitors to form filaments. We also explored 3 different mechanisms that create kinase-dead pseudokinases, including D2017A, which further emphasizes the highly synergistic role of key hydrophobic and hydrophilic/charged residues in the assembly of active LRRK2. We thus hypothesize that LRRK2 harbors a classical protein kinase switch mechanism that drives the dynamic activation of full-length LRRK2.


Asunto(s)
Dominio Catalítico , Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina/química , Simulación de Dinámica Molecular , Células HEK293 , Humanos , Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina/genética , Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina/metabolismo , Mutación Missense
9.
Sensors (Basel) ; 22(16)2022 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-36016015

RESUMEN

In radio-frequency (RF)-based device-free localization (DFL), the number of sensors acting as RF transmitters and receivers is crucial for accuracy and system costs. Two promising approaches for DFL have been identified in the past: radio tomographic imaging (RTI) and multi-static radar (MSR). RTI in its basic version requires many sensors for high accuracy, which increases the cost. In this paper, we show how RTI benefits from multipath propagation. By evaluating the direct and echo paths, we increase the coverage of the target area, and by utilizing UWB signals, the RTI system is less susceptible to multipath propagation. MSR maps reflections that occur within the target area to reflectors such as persons or other objects. MSR does not require that the person is located near a signal path. Both suggested methods exploit ultra-wideband (UWB) channel impulse response (CIR) measurements. CIR measurements and the modeling of multipath effects either increase the accuracy or reduce the required number of sensors for localization with RTI. We created a test setup and measure UWB CIRs at different positions with a commercially available off-the-shelf UWB radio chip, the Decawave DW1000. We compare the localization results of RTI, multipath-assisted (MA)-RTI, and MSR and investigate a combined approach. We show that RTI is improved by the analysis of multipath propagation; furthermore, MA-RTI results in a better performance compared to MSR: with 50% of all cases, the localization error is better than 0.82 m and in 80% of all cases 1.34 m. The combined approach results in the best localization result with 0.64 m in 50% of all cases.


Asunto(s)
Radar , Ondas de Radio , Humanos
10.
J Anesth ; 36(2): 246-253, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35044493

RESUMEN

PURPOSE: The purpose of this study was to outline the feasibility of continuous epidural analgesia in the treatment of failed back surgery syndrome (FBSS) or spinal stenosis. METHODS: We queried our prospective collected institutional database to include all consecutive patients, who underwent continuous epidural analgesia with accompanying intensive physiotherapeutic exercise within a timeframe of 4 years. Patients suffered from FBSS or spinal stenosis; protocolled continuous epidural analgesia was planned for 4 days within the framework of an inpatient multimodal pain therapy concept. The instillation technique of the epidural catheter, the capability to attend in accompanying physiotherapy, and the peri-interventional complications were evaluated. RESULTS: 153 patients with an average age of 57.4 years (± 11.9) were enrolled in this study. 105 patients suffered from FBSS and 48 patients had spinal stenosis. Overall, 148 patients (96.7%) reported the pain reduction and were able to perform daily intensified physiotherapeutic exercise. There were no serious adverse events, neither infection nor bleeding, no cardiopulmonary complication or permanent neurological deficits. The most common side effect was neurological impairment, such as numbness, dysesthesia, or weakness of the lower limbs with complete regression after flow rate adjustment. Patients with FBSS were more likely to develop dysesthesia (p = 0.007). CONCLUSIONS: Continuous epidural analgesia is feasible in patients with FBSS or spinal stenosis. This treatment enables extensive physiotherapeutic treatment even in patients with severe pain conditions and can be considered as an alternative to epidural injections. An increased complication rate in comparison to short-term perioperative or perinatal application was not observed.


Asunto(s)
Analgesia Epidural , Síndrome de Fracaso de la Cirugía Espinal Lumbar , Estenosis Espinal , Analgesia Epidural/efectos adversos , Síndrome de Fracaso de la Cirugía Espinal Lumbar/etiología , Síndrome de Fracaso de la Cirugía Espinal Lumbar/terapia , Estudios de Factibilidad , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Estenosis Espinal/complicaciones , Estenosis Espinal/cirugía
11.
Int J Legal Med ; 135(6): 2335-2345, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34591186

RESUMEN

Thorough postmortem investigations of fatalities following vaccination with coronavirus disease 2019 (COVID-19) vaccines are of great social significance. From 11.03.2021 to 09.06.2021, postmortem investigations of 18 deceased persons who recently received a vaccination against COVID-19 were performed. Vaxzevria was vaccinated in nine, Comirnaty in five, Spikevax in three, and Janssen in one person. In all cases, full autopsies, histopathological examinations, and virological analyses for the severe acute respiratory syndrome coronavirus 2 were carried out. Depending on the case, additional laboratory tests (anaphylaxis diagnostics, VITT [vaccine-induced immune thrombotic thrombocytopenia] diagnostics, glucose metabolism diagnostics) and neuropathological examinations were conducted. In 13 deceased, the cause of death was attributed to preexisting diseases while postmortem investigations did not indicate a causal relationship to the vaccination. In one case after vaccination with Comirnaty, myocarditis was found to be the cause of death. A causal relationship to vaccination was considered possible, but could not be proven beyond doubt. VITT was found in three deceased persons following vaccination with Vaxzevria and one deceased following vaccination with Janssen. Of those four cases with VITT, only one was diagnosed before death. The synopsis of the anamnestic data, the autopsy results, laboratory diagnostic examinations, and histopathological and neuropathological examinations revealed that VITT was the very likely cause of death in only two of the four cases. In the other two cases, no neuropathological correlate of VITT explaining death was found, while possible causes of death emerged that were not necessarily attributable to VITT. The results of our study demonstrate the necessity of postmortem investigations on all fatalities following vaccination with COVID-19 vaccines. In order to identify a possible causal relationship between vaccination and death, in most cases an autopsy and histopathological examinations have to be combined with additional investigations, such as laboratory tests and neuropathological examinations.


Asunto(s)
Vacunas contra la COVID-19 , Medicina Legal , Vacunación/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Anafilaxia/mortalidad , Autopsia , Causalidad , Causas de Muerte , Femenino , Alemania/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Miocarditis/mortalidad , Púrpura Trombocitopénica Idiopática/mortalidad
12.
Int J Legal Med ; 134(1): 369-374, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31664523

RESUMEN

The purpose of the present study was to test whether a new stage classification based on radiographic visibility of the periodontal ligament in lower third molars in a Chinese population can be used for the 18- and 21-year thresholds. A total of 1300 orthopantomograms, including equal numbers of northern Chinese males and females evenly distributed between the ages of 15 and 40 years, were analyzed. The stages were defined according to the visibility of periodontal ligament for the outer parts of lower third molar roots because the visibility status of the periodontal ligament between the roots of lower third molars is none valuable in many Chinese individuals. Stage 0 was first achieved at the age of 17.05 years in males and 17.46 years in females. The earliest appearance of stage 1 was 17.47 years in males and 17.86 years in females. Stage 2 was first observed in males at the age of 21.43 years and in females at the age of 21.96 years. The onset of stage 3 was first observed at the age of 25.83 years in males and 23.14 years in females. Compared with the stage classification of Olze et al., which also considers the mesial parts of the roots, the number of assessable cases could be significantly increased. Therefore, our novel approach is effective for age estimation in the Chinese population.


Asunto(s)
Determinación de la Edad por los Dientes/métodos , Odontología Forense/métodos , Tercer Molar/diagnóstico por imagen , Tercer Molar/crecimiento & desarrollo , Ligamento Periodontal/diagnóstico por imagen , Ligamento Periodontal/crecimiento & desarrollo , Adolescente , Adulto , Distribución por Edad , Pueblo Asiatico , Femenino , Humanos , Masculino , Mandíbula/diagnóstico por imagen , Mandíbula/crecimiento & desarrollo , Radiografía Panorámica , Distribución por Sexo , Adulto Joven
13.
Ren Fail ; 42(1): 1067-1075, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33076736

RESUMEN

INTRODUCTION: In the general population, hyperuricemia is associated with increased morbidity and mortality. Data on this association in hemodialysis patients is controversial. Moreover, it remains elusive whether serum uric acid (SUA) lowering therapy is associated with mortality. METHODS: Retrospective analysis of 601 patients on chronic hemodialysis therapy in five outpatient centers with a maximum follow-up of 100 and a mean follow-up of 41 months. Death was defined as primary endpoint. Cumulative survival was analyzed by Kaplan-Meier analysis and Cox regressions adjusted for age. FINDINGS: Cumulative survival rates were higher for those subjects with a higher than median SUA concentration both based on mean annual and baseline measurements (p < 0.05 each). There was no survival difference anymore after adjustment for age (p > 0.05 each). Stratification for SUA lowering therapy (allopurinol/febuxostat) had no impact on cumulative survival, neither in Kaplan Meier nor in Cox regression analyses (p > 0.05 each). Furthermore, Cox regression analysis excluded an increased cardiovascular mortality in subjects with hyperuricemia. DISCUSSION: In contrast to the general population, hyperuricemia is not associated with increased mortality in patients undergoing hemodialysis. Moreover, xanthine oxidase inhibition was not associated with a survival benefit in this analysis. These data do not support the use of SUA lowering medication in hemodialysis patients with asymptomatic hyperuricemia.


Asunto(s)
Gota/tratamiento farmacológico , Hiperuricemia/tratamiento farmacológico , Diálisis Renal , Insuficiencia Renal Crónica/mortalidad , Ácido Úrico/sangre , Anciano , Anciano de 80 o más Años , Alopurinol/uso terapéutico , Inhibidores Enzimáticos/uso terapéutico , Febuxostat/uso terapéutico , Femenino , Alemania/epidemiología , Gota/sangre , Supresores de la Gota/uso terapéutico , Humanos , Hiperuricemia/sangre , Masculino , Persona de Mediana Edad , Insuficiencia Renal Crónica/terapia , Estudios Retrospectivos , Análisis de Supervivencia
14.
Sensors (Basel) ; 20(24)2020 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-33322078

RESUMEN

In this paper, we propose a multipath-assisted device-free localization (DFL) system that includes magnitude and phase information (MAMPI). The DFL system employs ultra-wideband (UWB) channel impulse response (CIR) measurements, enabling the extraction of several multipath components (MPCs) and thereby benefits from multipath propagation. We propose a radio propagation model that calculates the effect on the received signal based on the position of a person within a target area. Additionally, we propose a validated error model for the measurements and explain the creation of different feature vectors and extraction of the MPCs from Decawave DW1000 CIR measurements. We evaluate the system via simulations of the position error probability and a measurement setup in an indoor scenario. We compare the performance of MAMPI to a conventional DFL system based on four sensor nodes that measures radio signal strength values. The combination of the magnitude and phase differences for the feature vectors results in a position error probability that is comparable to a conventional system but requires only two sensor nodes.

15.
Int J Legal Med ; 133(5): 1517-1528, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31104134

RESUMEN

Within medical age assessment practice, the indicator "medial clavicular ossification" constitutes crucial evidence capable of excluding age minority "beyond reasonable doubt" concerning age-disputed individuals doubtfully claiming children's rights during legal procedures. Yet, one of its characteristics affects the morphological variability including a fair amount of downright peculiar appearances. As a result, inexperienced examiners are tempted to classify actually not-assessable formations according to the two established developmental typologies of Schmeling et al. and Kellinghaus et al. being at the same time the most frequent systemic error of age-related clavicular taxation. Since a respective overview appears missing, the study extracts not-assessable shape variants of the medial collar bone from a large sample of 2820 male borderline-adults as seen from thin-slice, sternoclavicular computed tomography. The two already highlighted configurations "more than one, medial, secondary ossification centres" and "medial metaphyseal concavity" are found as the most commonly encountered features impeding reliable delineation of staging criteria. In accordance with previous literature, it is emphasized that "qualified" rating of extremitas sternalis claviculae within age assessment practice presupposes "knowledge about the diversity of [its] anatomic shape variants."


Asunto(s)
Determinación de la Edad por el Esqueleto/métodos , Clavícula/diagnóstico por imagen , Clavícula/crecimiento & desarrollo , Osteogénesis , Articulación Esternoclavicular/diagnóstico por imagen , Adulto , Afganistán , Argelia , Epífisis/diagnóstico por imagen , Epífisis/crecimiento & desarrollo , Gambia , Humanos , Masculino , Menores , Tomografía Computarizada Multidetector , Nigeria , Pakistán , Refugiados , Somalia
16.
Int J Legal Med ; 133(3): 921-930, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30790037

RESUMEN

Regressive dental changes appear to be suitable for age assessment in living adults. In 2012, Olze et al. showed that several criteria presented by Gustafson for extracted teeth can also be applied to orthopantomograms. The objective of this study was to test the applicability and reliability of this method in a Chinese population. For this purpose, 1300 orthopantomograms of 650 female and 650 male Chinese aged between 15 and 40 years were evaluated. The characteristics of secondary dentin formation, periodontal recession, attrition, and cementum apposition were reviewed in all the mandibular premolars. The sample was split into a training and test dataset. Based on the training set, the correlation of the individual characteristics with chronological age was studied with a stepwise multiple regression analysis, in which individual characteristics formed the independent variable. According to the results, the R values amounted to 0.80 to 0.83; the standard error of estimate was 4.29 to 4.75 years. By analyzing the test dataset, the accuracy of the present study, Olze's and Timme's formulas were determined by the difference between the estimated dental age (DA) and chronological age (CA). Taking both mean differences and mean absolute differences into account, the Chinese age estimation formula did not always perform better compared with Olze's and Timme's formulas for both males and females. It was concluded that this method can be used in Chinese individuals for age assessment. However, the applicability of the method is limited by the quality of the X-ray images, and the method should only be applied by experienced forensic odontologists.


Asunto(s)
Determinación de la Edad por los Dientes/métodos , Adolescente , Adulto , Pueblo Asiatico , Diente Premolar/diagnóstico por imagen , China , Cemento Dental/diagnóstico por imagen , Dentina Secundaria/diagnóstico por imagen , Femenino , Recesión Gingival/clasificación , Recesión Gingival/diagnóstico por imagen , Humanos , Masculino , Radiografía Panorámica , Análisis de Regresión , Atrición Dental/clasificación , Atrición Dental/diagnóstico por imagen , Adulto Joven
17.
Br J Clin Pharmacol ; 84(9): 1941-1949, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29665130

RESUMEN

AIMS: Previous pharmacokinetic characterization of a transporter probe cocktail containing digoxin (P-gp), furosemide (OAT1, OAT3), metformin (OCT2, MATE1, MATE2-K) and rosuvastatin (OATP1B1, OATP1B3, BCRP) in healthy subjects showed increases in rosuvastatin systemic exposure compared to rosuvastatin alone. In this trial, the doses of metformin and furosemide as putative perpetrators were reduced to eliminate their drug-drug interaction (DDI) with rosuvastatin. METHODS: In a randomized, open-label, single-centre, five-treatment, five-period crossover trial, 30 healthy male subjects received as reference treatments separately 0.25 mg digoxin, 1 mg furosemide, 10 mg metformin and 10 mg rosuvastatin, and as test treatment all four drugs administered together as a cocktail. Primary pharmacokinetic endpoints were AUC0-tz (area under the plasma concentration-time curve from time zero to the last quantifiable concentration) and Cmax (maximum plasma concentration) of each probe drug. RESULTS: Geometric mean ratios and 90% confidence intervals of test (cocktail) to reference (single drug) for AUC0-tz were 96.4% (88.2-105.3%) for digoxin, 102.6% (93.8-112.3%) for furosemide, 97.5% (93.5-101.6%) for metformin and 105.0% (96.4-114.4%) for rosuvastatin, indicating lack of interaction. The same analysis for Cmax and for pharmacokinetic parameters of urinary excretion of all cocktail components also indicated no DDI. CONCLUSIONS: Digoxin (0.25 mg), furosemide (1 mg), metformin (10 mg) and rosuvastatin (10 mg) exhibit no mutual pharmacokinetic interactions and are well tolerated administered as a cocktail. The cocktail is thus optimized and has the potential to be used as a screening tool for clinical investigation of transporter-mediated DDI.


Asunto(s)
Desarrollo de Medicamentos/métodos , Interacciones Farmacológicas , Proteínas de Transporte de Membrana/metabolismo , Adulto , Área Bajo la Curva , Estudios Cruzados , Digoxina/administración & dosificación , Digoxina/metabolismo , Digoxina/farmacocinética , Relación Dosis-Respuesta a Droga , Furosemida/administración & dosificación , Furosemida/metabolismo , Furosemida/farmacocinética , Voluntarios Sanos , Humanos , Masculino , Metformina/administración & dosificación , Metformina/metabolismo , Metformina/farmacocinética , Persona de Mediana Edad , Eliminación Renal , Rosuvastatina Cálcica/administración & dosificación , Rosuvastatina Cálcica/metabolismo , Rosuvastatina Cálcica/farmacocinética , Adulto Joven
18.
Int J Legal Med ; 132(1): 243-248, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29086054

RESUMEN

Granulomatosis with polyangiitis (GPA), formerly known as Wegener's granulomatosis, is the most common form of life-threatening small-vessel vasculitis. Although its exact pathogenesis remains unclear, GPA is believed to belong to the wide complex of autoimmune diseases due to the presence of anti-neutrophil cytoplasmatic antibodies with cytoplasmic staining pattern (c-ANCA) that is expressed in activated neutrophils. GPA predominantly manifests at the upper and lower respiratory tract and the kidneys, but the impairment of multiple organ systems is possible as well. The so-called classical clinical triad of GPA comprises sinusitis, pneumonia, and glomerulonephritis. Despite the fact that there is an elevated risk of mortality for patients suffering from GPA, sudden death due to GPA is a rare and difficult differential diagnosis of sudden natural death in forensic case work. In the present article, the rare case of a 41-year-old male, who died of a sudden death due to previously undiagnosed GPA, is demonstrated. The final diagnosis was feasible by close interdisciplinary collaboration, considering the entire body of findings obtained during autopsy, histopathological investigation, and analysis of the clinical records. Therefore, it remains necessary to point out that especially for rare causes of death, interdisciplinary collaboration is essential in order to concretize the cause of death and exclude rare differential diagnoses of sudden unexpected death of hospitalized patients in forensic case work.


Asunto(s)
Muerte Súbita/etiología , Granulomatosis con Poliangitis/diagnóstico , Adulto , Proteína C-Reactiva/análisis , Humanos , Riñón/patología , Pulmón/patología , Ganglios Linfáticos/patología , Masculino , Miocardio/patología , Insuficiencia Respiratoria/etiología
19.
Int J Legal Med ; 132(2): 629-636, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28944440

RESUMEN

In the past, numerous studies have documented the possibility of intraindividual differing appearances of the paired age-marker "medial clavicular ossification" in borderline adults. However, the extent of the divergences is rarely mentioned. Against that the article describes this phenomenon from a large sample of 2595 male persons by means of thin-slice CT imaging of the sternoclavicular regions. For determining the ossification stage of the medial clavicles, the two accepted classifications by Schmeling et al. (five main stages) and Kellinghaus et al. (six substages) were applied and buildings deviating from that labelled as atypical "norm variants". The longstanding observation could be confirmed that intraindividual stage discrepancies of this age indicator are generally moderate and do not exceed one main stage or two substages of the respective classifications. It is concluded that stage determination should be scrutinized, if a dissimilarity seems to show larger differences.


Asunto(s)
Determinación de la Edad por el Esqueleto/métodos , Clavícula/diagnóstico por imagen , Osteogénesis , Clavícula/crecimiento & desarrollo , Epífisis/diagnóstico por imagen , Epífisis/crecimiento & desarrollo , Humanos , Masculino , Tomografía Computarizada por Rayos X
20.
Int J Legal Med ; 132(2): 617-622, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28812130

RESUMEN

The purpose of the present research is to study the radiographic visibility of the periodontal ligament in third molars from a northern Chinese population to determine if this methodology could be used for the 18-year threshold. A total of 1300 conventional orthopantomograms from 650 males and 650 females of northern Chinese subjects aged between 15 and 40 years were analyzed. The radiographic visibility of the periodontal membrane of fully mineralized third molars was assessed using the stages described by Olze et al. (2010). Stage 0 first appeared at the age of 17.05 years in males and at the age of 18.76 years in females. Stage 1 was first detected at 18.52 years in males and 19.59 years in females. Stage 2 was first achieved by males at the age of 22.33 years and by females at the age of 21.37 years. The earliest appearance of stage 3 was 26.85 years in males and 24.92 years in females. If stage 1 is determined, it is possible to prove that an individual has already attained the age of 18 years. Stages 2 and 3 can be used to determine that a person is over 21 years of age. However, it should also be noted that in 271 cases of tooth 38 and 255 cases of tooth 48, the visibility stage could not be reliably assessed because of fused roots or narrowed furcations. Therefore, this method seems to be of limited value for age estimation in the Chinese population.


Asunto(s)
Determinación de la Edad por los Dientes/métodos , Tercer Molar/diagnóstico por imagen , Ligamento Periodontal/diagnóstico por imagen , Radiografía Panorámica , Adolescente , Adulto , Pueblo Asiatico , China , Femenino , Humanos , Masculino , Tercer Molar/crecimiento & desarrollo , Ligamento Periodontal/crecimiento & desarrollo , Calcificación de Dientes , Adulto Joven
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