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1.
Sleep Breath ; 28(4): 1691-1699, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38744804

RESUMEN

PURPOSE: The cardiorespiratory polysomnography (PSG) is an expensive and limited resource. The Sleepiz One + is a novel radar-based contactless monitoring device that can be used e.g. for longitudinal detection of nocturnal respiratory events. The present study aimed to compare the performance of the Sleepiz One + device to the PSG regarding the accuracy of apnea-hypopnea index (AHI). METHODS: From January to December 2021, a total of 141 adult volunteers who were either suspected of having sleep apnea or who were healthy sleepers took part in a sleep study. This examination served to validate the Sleepiz One + device in the presence and absence of additional SpO2 information. The AHI determined by the Sleepiz One + monitor was estimated automatically and compared with the AHI derived from manual PSG scoring. RESULTS: The correlation between the Sleepiz-AHI and the PSG-AHI with and without additional SpO2 measurement was rp = 0.94 and rp = 0,87, respectively. In general, the Bland-Altman plots showed good agreement between the two methods of AHI measurement, though their deviations became larger with increasing sleep-disordered breathing. Sensitivity and specificity for recordings without additional SpO2 was 85% and 88%, respectively. Adding a SpO2 sensor increased the sensitivity to 88% and the specificity to 98%. CONCLUSION: The Sleepiz One + device is a valid diagnostic tool for patients with moderate to severe OSA. It can also be easily used in the home environment and is therefore beneficial for e.g. immobile and infectious patients. TRIAL REGISTRATION NUMBER AND DATE OF REGISTRATION FOR PROSPECTIVELY REGISTERED TRIALS: This study was registered on clinicaltrials.gov (NCT04670848) on 2020-12-09.


Asunto(s)
Polisomnografía , Radar , Síndromes de la Apnea del Sueño , Humanos , Masculino , Femenino , Polisomnografía/instrumentación , Adulto , Persona de Mediana Edad , Síndromes de la Apnea del Sueño/diagnóstico , Radar/instrumentación , Sensibilidad y Especificidad , Reproducibilidad de los Resultados
2.
J Asthma ; 56(7): 687-692, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-29972658

RESUMEN

BACKGROUND: Pulsus paradoxus (PP) represents increased fluctuation of systolic pressure during the respiratory cycle. PP increases in pathologic conditions, including asthma and other obstructive airways diseases. Respiratory waveform variation (RWV) represents arterial-waveform baseline variability resulting from intra-pleural pressure changes during the respiratory cycle in the presence of airway obstruction. It is not known whether RWV influences manual PP measurement using a sphygmomanometer and stethoscope. METHODS: We performed an observational study in six healthy adults. Participants performed tidal-breathing through a breathing apparatus with pre-determined inspiratory (0-45.6 cm H2O) and expiratory (0-24.4 cm H2O) resistance levels for a total of 23 data sets per participant. PP was measured from continuous radial artery pressure recordings as the absolute difference between maximum and minimum systolic pressure levels during a complete respiratory cycle. RESULTS: In this study, PP values measured without applied airway resistance exceeded 10 mmHg, the traditional definition of PP, in five of the six participants. Manual measurement of PP would not be possible at greater RWV because the maximum diastolic pressure exceeded minimum systolic pressure during RWV. CONCLUSIONS: PP in normal adults may exceed 10 mmHg, and RWV may be of sufficient magnitude to preclude manual PP measurement.


Asunto(s)
Asma/fisiopatología , Presión Sanguínea , Respiración , Adulto , Humanos , Masculino , Esfigmomanometros , Adulto Joven
3.
Chem Rev ; 116(13): 7463-500, 2016 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-27380438

RESUMEN

Water is the most abundant liquid on earth and also the substance with the largest number of anomalies in its properties. It is a prerequisite for life and as such a most important subject of current research in chemical physics and physical chemistry. In spite of its simplicity as a liquid, it has an enormously rich phase diagram where different types of ices, amorphous phases, and anomalies disclose a path that points to unique thermodynamics of its supercooled liquid state that still hides many unraveled secrets. In this review we describe the behavior of water in the regime from ambient conditions to the deeply supercooled region. The review describes simulations and experiments on this anomalous liquid. Several scenarios have been proposed to explain the anomalous properties that become strongly enhanced in the supercooled region. Among those, the second critical-point scenario has been investigated extensively, and at present most experimental evidence point to this scenario. Starting from very low temperatures, a coexistence line between a high-density amorphous phase and a low-density amorphous phase would continue in a coexistence line between a high-density and a low-density liquid phase terminating in a liquid-liquid critical point, LLCP. On approaching this LLCP from the one-phase region, a crossover in thermodynamics and dynamics can be found. This is discussed based on a picture of a temperature-dependent balance between a high-density liquid and a low-density liquid favored by, respectively, entropy and enthalpy, leading to a consistent picture of the thermodynamics of bulk water. Ice nucleation is also discussed, since this is what severely impedes experimental investigation of the vicinity of the proposed LLCP. Experimental investigation of stretched water, i.e., water at negative pressure, gives access to a different regime of the complex water diagram. Different ways to inhibit crystallization through confinement and aqueous solutions are discussed through results from experiments and simulations using the most sophisticated and advanced techniques. These findings represent tiles of a global picture that still needs to be completed. Some of the possible experimental lines of research that are essential to complete this picture are explored.

4.
Cancers (Basel) ; 16(6)2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38539492

RESUMEN

In patients with primary central nervous system lymphoma (PCNSL), the choice of surgical strategy for histopathologic assessments is still controversial, particularly in terms of preoperative corticosteroid (CS) therapy. To provide further evidence for clinical decision-making, we retrospectively analyzed data from 148 consecutive patients who underwent surgery at our institution. Although patients treated with corticosteroids preoperatively were significantly more likely to require a second or third biopsy (p = 0.049), it was only necessary in less than 10% of the cases with preoperative (but discontinued) corticosteroid treatment. Surprisingly, diagnostic accuracy was significantly lower when patients were treated with anticoagulation or dual antiplatelet therapy (p = 0.015). Preoperative CSF sampling did not provide additional information but was associated with delayed surgery (p = 0.02). In conclusion, preoperative CS therapy can challenge the histological diagnosis of PCNSL. At the same time, our data suggest that preoperative CS treatment only presents a relative contraindication for early surgical intervention. If a definitive diagnosis cannot be made after the first surgical intervention, the timing of a repeat biopsy after the discontinuation of CS remains a case-by-case decision. The effect of anticoagulation and dual antiplatelet therapy on diagnostic accuracy might have been underestimated and should be examined closely in future investigations.

7.
Artículo en Inglés | MEDLINE | ID: mdl-37872263

RESUMEN

PURPOSE: In childhood and adolescence, cross-sectional imaging, most commonly computed tomography (CT), is often performed for advanced diagnosis of joint injuries of the distal lower leg and upper ankle. Due to radiation exposure, the need for CT remains controversial, as these injuries follow stereotypies and usually have a similar course. Alternatively, the performance of magnetic resonance imaging (MRI) is also discussed. Since radiation sensitivity at this young age is much higher than in adults, an effort must be to minimize radiation exposure according to as low as reasonably achievable (ALARA) principles. The aim of this survey is to evaluate the current procedure in Germany in the diagnosis of pediatric injuries of the distal lower leg and upper ankle. METHODS: For data collection, a survey entitled "CT in fractures of the ankle joint in childhood and adolescence: subject of the survey are injuries between 8 and 15 years of age" of the Section of Pediatric Traumatology in the German Association of Trauma Surgery was sent to all members via the distribution list of the German Society of Orthopedics and Traumatology and the distribution list of the German Society of Pediatric Surgery in a period from September 20, 2022-December 21, 2022. The survey included a total of 21 questions. Target groups were trauma and pediatric surgeons and orthopedic surgeons working in the hospital and in practice. RESULTS: A total of 525 participants took part in the survey: ultrasound diagnostics are used by almost 25% and the Ottawa Ankle Rules by over 50% always or in most cases. A conventional x-ray is always or most often used by over 90%. CT imaging is rarely used by 88.57%, mainly for surgical planning or analysis of fracture progression. 69.9% report that their radiology department uses a pediatric protocol for CT exams; 25.71% do not know if this is the case. MRI imaging is also used infrequently by 89.33%, mostly to identify associated injuries. Overall, CT imaging is chosen by 55.62% and MRI imaging by 35.24% as the sectional imaging modality for suspected fractures; 95.05% consider sectional imaging useful for a triplane fracture, 59.24% for a two-plane fracture, 41.71% for a Salter-Harris type III/IV injury, and 8% for a Salter-Harris type I/II injury. CONCLUSION: The survey showed that the conventional X-ray is still the gold standard. Interestingly, more than half of the respondents regularly use the Ottawa Ankle Rules, and diagnostics using ultrasound are also used by almost a quarter. Awareness of radiation protection in children exists, although a quarter of all participants do not know the extent to which their radiology department has a specific pediatric protocol for CT imaging. Cross-sectional imaging is performed on a regular basis. Regarding the actual extent of imaging, there is a clear divergence between theory and practice.

8.
J Alzheimers Dis ; 94(1): 259-279, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37248900

RESUMEN

BACKGROUND: Atrophy of the medial temporal lobe (MTL) is a biological characteristic of Alzheimer's disease (AD) and can be measured by segmentation of magnetic resonance images (MRI). OBJECTIVE: To assess the clinical utility of automated volumetry in a cognitively well-defined and biomarker-classified multi-center longitudinal predementia cohort. METHODS: We used Automatic Segmentation of Hippocampal Subfields (ASHS) to determine MTL morphometry from MRI. We harmonized scanner effects using the recently developed longitudinal ComBat. Subjects were classified according to the A/T/N system, and as normal controls (NC), subjective cognitive decline (SCD), or mild cognitive impairment (MCI). Positive or negative values of A, T, and N were determined by cerebrospinal fluid measurements of the Aß42/40 ratio, phosphorylated and total tau. From 406 included subjects, longitudinal data was available for 206 subjects by stage, and 212 subjects by A/T/N. RESULTS: Compared to A-/T-/N- at baseline, the entorhinal cortex, anterior and posterior hippocampus were smaller in A+/T+orN+. Compared to NC A- at baseline, these subregions were also smaller in MCI A+. Longitudinally, SCD A+ and MCI A+, and A+/T-/N- and A+/T+orN+, had significantly greater atrophy compared to controls in both anterior and posterior hippocampus. In the entorhinal and parahippocampal cortices, longitudinal atrophy was observed only in MCI A+ compared to NC A-, and in A+/T-/N- and A+/T+orN+ compared to A-/T-/N-. CONCLUSION: We found MTL neurodegeneration largely consistent with existing models, suggesting that harmonized MRI volumetry may be used under conditions that are common in clinical multi-center cohorts.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Enfermedad de Alzheimer/patología , Lóbulo Temporal/diagnóstico por imagen , Lóbulo Temporal/patología , Corteza Entorrinal/diagnóstico por imagen , Corteza Entorrinal/patología , Disfunción Cognitiva/patología , Hipocampo/diagnóstico por imagen , Hipocampo/patología , Imagen por Resonancia Magnética/métodos , Atrofia/patología
9.
Cell Stem Cell ; 30(5): 706-721.e8, 2023 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-37098346

RESUMEN

Inter-patient variability and the similarity of healthy and leukemic stem cells (LSCs) have impeded the characterization of LSCs in acute myeloid leukemia (AML) and their differentiation landscape. Here, we introduce CloneTracer, a novel method that adds clonal resolution to single-cell RNA-seq datasets. Applied to samples from 19 AML patients, CloneTracer revealed routes of leukemic differentiation. Although residual healthy and preleukemic cells dominated the dormant stem cell compartment, active LSCs resembled their healthy counterpart and retained erythroid capacity. By contrast, downstream myeloid progenitors constituted a highly aberrant, disease-defining compartment: their gene expression and differentiation state affected both the chemotherapy response and leukemia's ability to differentiate into transcriptomically normal monocytes. Finally, we demonstrated the potential of CloneTracer to identify surface markers misregulated specifically in leukemic cells. Taken together, CloneTracer reveals a differentiation landscape that mimics its healthy counterpart and may determine biology and therapy response in AML.


Asunto(s)
Leucemia Mieloide Aguda , Multiómica , Humanos , Leucemia Mieloide Aguda/genética , Diferenciación Celular , Células Madre Neoplásicas/metabolismo
10.
Int J Chron Obstruct Pulmon Dis ; 17: 2553-2566, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36304970

RESUMEN

Purpose: To investigate changes in quantitative CT analysis (QCT) and pulmonary function tests (PFT) in pulmonary emphysema patients who required premature removal of endobronchial valves (EBV). Patients and Methods: Our hospital's medical records listed 274 patients with high-grade COPD (GOLD stages 3 and 4) and pulmonary emphysema who were treated with EBV to reduce lung volume. Prior to intervention, a complete evaluation was performed that included quantitative computed tomography analysis (QCT) of scans acquired at full inspiration and full expiration, pulmonary function tests (PFT), and paraclinical findings (6-minute walking distance test (6MWDT) and quality of life questionnaires). In 41 of these 274 patients, EBV treatment was unsuccessful and the valves had to be removed for various reasons. A total of 10 of these 41 patients ventured a second attempt at EBV therapy and underwent complete reevaluation. In our retrospective study, results from three time points were compared: Before EBV implantation (BL), after EBV implantation (TP2), and after EBV explantation (TP3). QCT parameters included lung volume, total emphysema score (TES, ie, the emphysema index) and the 15th percentile of lung attenuation (P15) for the whole lung and each lobe separately. Differences in these parameters between inspiration and expiration were calculated (Vol. Diff (%), TES Diff (%), P15 Diff (%)). The results of PFT and further clinical tests were taken from the patient's records. Results: We found persistent therapy effect in the target lobe even after valve explantation together with a compensatory hyperinflation of the rest of the lung. As a result of these two divergent effects, the volume of the total lung remained rather constant. Furthermore, there was a slight deterioration of the emphysema score for the whole lung, whereas the TES of the target lobe persistently improved. Conclusion: Interestingly, we found evidence that, contrary to our expectations, unsuccessful EBV therapy can have a persistent positive effect on target lobe QCT scores.


Asunto(s)
Enfisema , Enfermedad Pulmonar Obstructiva Crónica , Enfisema Pulmonar , Humanos , Enfisema Pulmonar/diagnóstico por imagen , Enfisema Pulmonar/cirugía , Estudios Retrospectivos , Calidad de Vida , Volumen Espiratorio Forzado , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico por imagen , Pruebas de Función Respiratoria , Tomografía Computarizada por Rayos X/métodos , Broncoscopía , Resultado del Tratamiento
11.
PLoS One ; 10(8): e0135712, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26270961

RESUMEN

INTRODUCTION: The effects of manipulated dental occlusion on body posture has been investigated quite often and discussed controversially in the literature. Far less attention has been paid to the influence of dental occlusion position on human movement. If human movement was analysed, it was mostly while walking and not while running. This study was therefore designed to identify the effect of lower jaw positions on running behaviour according to different dental occlusion positions. METHODS: Twenty healthy young recreational runners (mean age = 33.9±5.8 years) participated in this study. Kinematic data were collected using an eight-camera Vicon motion capture system (VICON Motion Systems, Oxford, UK). Subjects were consecutively prepared with four different dental occlusion conditions in random order and performed five running trials per test condition on a level walkway with their preferred running shoes. Vector based pattern recognition methods, in particular cluster analysis and support vector machines (SVM) were used for movement pattern identification. RESULTS: Subjects exhibited unique movement patterns leading to 18 clusters for the 20 subjects. No overall classification of the splint condition could be observed. Within individual subjects different running patterns could be identified for the four splint conditions. The splint conditions lead to a more symmetrical running pattern than the control condition. DISCUSSION: The influence of an occlusal splint on running pattern can be confirmed in this study. Wearing a splint increases the symmetry of the running pattern. A more symmetrical running pattern might help to reduce the risk of injuries or help in performance. The change of the movement pattern between the neutral condition and any of the three splint conditions was significant within subjects but not across subjects. Therefore the dental splint has a measureable influence on the running pattern of subjects, however subjects individuality has to be considered when choosing the optimal splint condition for a specific subject.


Asunto(s)
Mandíbula/anatomía & histología , Mandíbula/fisiología , Carrera/fisiología , Adulto , Oclusión Dental , Femenino , Voluntarios Sanos , Humanos , Masculino , Ferulas Oclusales , Reconocimiento de Normas Patrones Automatizadas/métodos , Máquina de Vectores de Soporte
12.
Acta Crystallogr C ; 60(Pt 7): m320-3, 2004 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15237147

RESUMEN

Complexes of the composition trans-[Pd(L)2(OAc)2] have been postulated as intermediates during cyclopalladation. The first structural characterization of such a precursor has now been achieved and its role in the reaction sequence has been established. Diacetato-kappa2O-bis[(S)-1-(4-fluorophenyl)ethylamine-kappaN]palladium(II), [Pd(O2CMe)2(4-FC6H3CHMeNH2)2] or [Pd(C2H3O2)2(C8H10FN)2], (I), was obtained from palladium(II) acetate and (S)-NH2CHMeC6H3F-4 in a 1:2 molar ratio. The intermediate was then reacted with additional palladium(II) acetate to give the acetate-bridged dinuclear complex di-mu-acetato-kappa4O:O'-bis[[(S)-2-(1-aminoethyl)-5-fluorophenyl-kappa2C1,N]palladium(II)] benzene hemisolvate, [Pd(4-FC6H3CHMeNH2)2(mu-O2CMe)]2.0.5C6H6 or [Pd2(C8H9FN)2(C2H3O2)2].0.5C6H6, (II).

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