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1.
J Clin Med ; 12(3)2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36769819

RESUMEN

The development of a progressive phenotype of interstitial lung disease (ILD) is still unpredictable. Whereas tools to predict mortality in ILD exist, scores to predict disease progression are missing. The aim of this study was to investigate whether baseline serum KL-6 as an established marker to assess disease activity in ILD, alone or in combination with clinical variables, could improve stratification of ILD patients according to progression risk at any time. Consecutive patients with fibrotic ILD, followed at our institution between 2008 and 2015, were investigated. Disease progression was defined as relative decline of ≥10% in forced vital capacity (FVC) or ≥15% in diffusing capacity of the lung for carbon monoxide (DLco)% from baseline at any time. Serum KL-6 was measured using an automated immunoassay (Fujirebio Europe, Gent, Belgium). A stepwise logistic regression was performed to select variables to be included in the score. A total of 205 patients (49% idiopathic pulmonary fibrosis (IPF), 51% fibrotic nonspecific interstitial pneumonia (NSIP)) were included, of them 113 (55%) developed disease progression during follow up. Male gender (G) and serum KL-6 strata (K) were significant predictors of progression at regression analysis and were included in the GK score. A threshold of 2 GK score points was best for discriminating patients at high risk versus low risk to develop disease progression at any time. Serum KL-6 concentration, alone or combined in a simple score with gender, allows an effective stratification of ILD patients for risk of disease progression at any time.

2.
Immunobiology ; 227(5): 152258, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35998415

RESUMEN

INTRODUCTION: IL-9, mainly produced by T helper 9 (Th9) cells, promotes allergic airway inflammation and remodeling through the interaction with its receptor (IL-9R). Th9 cells and IL-9 have also been implicated in tissue fibrosis and autoimmunity pathways. However, the role of IL-9/IL-9R in the pathogenesis of interstitial lung disease (ILD) is unknown. AIM: To evaluate IL-9/IL-9R expression in bronchoalveolar lavage fluid (BALF) lymphocytes of patients with various ILDs. METHODS: Consecutive patients with ILD, who underwent BAL for diagnostic purposes, were studied. As control group, consecutive patients without evidence of ILD were included. Immunocytochemical staining of BALF lymphocytes for IL-9 and IL-9R was performed and evaluated by two independent readers. RESULTS: 45 patients, of them 8 had idiopathic pulmonary fibrosis (IPF), 12 nonspecific interstitial pneumonia (NSIP), 10 sarcoidosis, 9 hypersensitivity pneumonitis (HP), 6 cryptogenic organizing pneumonia (COP), and 24 controls were studied. In the ILD group, the highest BALF lymphocyte count was seen in HP followed by NSIP, COP, sarcoidosis, and IPF (p < 0.05 for HP vs IPF). The highest percentages of IL-9 and IL-9R positive lymphocytes were seen in COP. Conversely, NSIP showed the lowest rate of IL-9, and sarcoidosis the lowest rate of IL-9R positive lymphocytes. Only in NSIP, a direct correlation between IL and 9 and IL-9R positive lymphocytes was seen (r = 0.639, p = 0.025). CONCLUSION: BALF lymphocytes IL-9 and IL-9R expression differs between various ILDs and could reflect different pathogenetic mechanisms.


Asunto(s)
Fibrosis Pulmonar Idiopática , Enfermedades Pulmonares Intersticiales , Sarcoidosis , Lavado Broncoalveolar , Líquido del Lavado Bronquioalveolar , Humanos , Interleucina-9 , Enfermedades Pulmonares Intersticiales/diagnóstico , Linfocitos/metabolismo , Receptores de Interleucina-9
3.
Transl Psychiatry ; 11(1): 392, 2021 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-34282129

RESUMEN

The COVID-19 pandemic and resulting measures can be regarded as a global stressor. Cross-sectional studies showed rather negative impacts on people's mental health, while longitudinal studies considering pre-lockdown data are still scarce. The present study investigated the impact of COVID-19 related lockdown measures in a longitudinal German sample, assessed since 2017. During lockdown, 523 participants completed additional weekly online questionnaires on e.g., mental health, COVID-19-related and general stressor exposure. Predictors for and distinct trajectories of mental health outcomes were determined, using multilevel models and latent growth mixture models, respectively. Positive pandemic appraisal, social support, and adaptive cognitive emotion regulation were positively, whereas perceived stress, daily hassles, and feeling lonely negatively related to mental health outcomes in the entire sample. Three subgroups ("recovered," 9.0%; "resilient," 82.6%; "delayed dysfunction," 8.4%) with different mental health responses to initial lockdown measures were identified. Subgroups differed in perceived stress and COVID-19-specific positive appraisal. Although most participants remained mentally healthy, as observed in the resilient group, we also observed inter-individual differences. Participants' psychological state deteriorated over time in the delayed dysfunction group, putting them at risk for mental disorder development. Consequently, health services should especially identify and allocate resources to vulnerable individuals.


Asunto(s)
COVID-19 , Salud Mental , Control de Enfermedades Transmisibles , Estudios Transversales , Alemania/epidemiología , Humanos , Pandemias , Factores Protectores , SARS-CoV-2
4.
Eur Arch Psychiatry Clin Neurosci ; 271(6): 1035-1051, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32683526

RESUMEN

Resilience is the maintenance and/or quick recovery of mental health during and after periods of adversity. It is conceptualized to result from a dynamic process of successful adaptation to stressors. Up to now, a large number of resilience factors have been proposed, but the mechanisms underlying resilience are not yet understood. To shed light on the complex and time-varying processes of resilience that lead to a positive long-term outcome in the face of adversity, the Longitudinal Resilience Assessment (LORA) study has been established. In this study, 1191 healthy participants are followed up at 3- and 18-month intervals over a course of 4.5 years at two study centers in Germany. Baseline and 18-month visits entail multimodal phenotyping, including the assessment of mental health status, sociodemographic and lifestyle variables, resilience factors, life history, neuropsychological assessments (of proposed resilience mechanisms), and biomaterials (blood for genetic and epigenetic, stool for microbiome, and hair for cortisol analysis). At 3-monthly online assessments, subjects are monitored for subsequent exposure to stressors as well as mental health measures, which allows for a quantitative assessment of stressor-dependent changes in mental health as the main outcome. Descriptive analyses of mental health, number of stressors including major life events, daily hassles, perceived stress, and the ability to recover from stress are here presented for the baseline sample. The LORA study is unique in its design and will pave the way for a better understanding of resilience mechanisms in humans and for further development of interventions to successfully prevent stress-related disorder.


Asunto(s)
Resiliencia Psicológica , Estrés Psicológico , Alemania , Humanos , Estudios Longitudinales , Estrés Psicológico/psicología
6.
Phys Med Biol ; 64(22): 225020, 2019 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-31374558

RESUMEN

The clinical implementation of a variable relative biological effectiveness (RBE) in proton therapy is currently controversially discussed. Initial clinical evidence indicates a variable proton RBE, which needs to be verified. In this study, a radiation response modelling framework for assessing clinical RBE variability is established. It was applied to four selected glioma patients (grade III) treated with adjuvant radio(chemo)therapy and who developed late morphological image changes on T1-weighted contrast-enhanced (T1w-CE) magnetic resonance (MR) images within approximately two years of recurrence-free follow-up. The image changes were correlated voxelwise with dose and linear energy transfer (LET) values using univariable and multivariable logistic regression analysis. The regression models were evaluated by the area-under-the-curve (AUC) method performing a leave-one-out cross validation. The tolerance dose TD50 at which 50% of patient voxels experienced toxicity was interpolated from the models. A Monte Carlo (MC) model was developed to simulate dose and LET distributions, which includes variance reduction (VR) techniques to decrease computation time. Its reliability and accuracy were evaluated based on dose calculations of the clinical treatment planning system (TPS) as well as absolute dose measurements performed in the patient specific quality assurance. Morphological image changes were related to a combination of dose and LET. The multivariable models revealed cross-validated AUC values of up to 0.88. The interpolated TD50 curves decreased with increasing LET indicating an increase in biological effectiveness. The MC model reliably predicted average TPS dose within the clinical target volume as well as absolute water phantom dose measurements within 2% accuracy using dedicated VR settings. The observed correlation of dose and LET with late brain tissue damage suggests considering RBE variability for predicting chronic radiation-induced brain toxicities. The MC model simulates radiation fields in patients precisely and time-efficiently. Hence, this study encourages and enables in-depth patient evaluation to assess the variability of clinical proton RBE.


Asunto(s)
Método de Montecarlo , Terapia de Protones , Efectividad Biológica Relativa , Encéfalo/efectos de la radiación , Humanos , Transferencia Lineal de Energía , Fantasmas de Imagen , Terapia de Protones/efectos adversos , Traumatismos por Radiación/etiología , Planificación de la Radioterapia Asistida por Computador , Reproducibilidad de los Resultados
8.
Neurochem Int ; 125: 7-15, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30716357

RESUMEN

Altered endocannabinoid (eCB) signalling is suggested as an important contributor to the pathophysiology of depression. To further elucidate this, we conducted a study using a genetic rat model of depression, the Flinders Sensitive Line (FSL), and their controls, the Flinders Resistant Line (FRL) rats. Plasma, right and left prefrontal cortex, and hippocampus were isolated from FSL and FRL rats. We analyzed each region for the eCB anandamide (AEA) and 2-arachidonoylglycerol (2-AG) levels by liquid chromatography/multiple reaction monitoring (LC/MRM), mRNA and protein levels of the cannabinoid type 1 receptor (CB1R), fatty acid amide hydrolase (FAAH) and monoacyl glycerol lipase (MAGL) by real time qPCR and Western blotting. Content of 2-AG was lower in the left side of the hippocampus and prefrontal cortex in FSL rats compared to FRL rats. Inversely, levels of AEA were higher in right hippocampus than in left hippocampus. In plasma, AEA levels were increased and 2-AG decreased. Cannabinoid receptor 1 (Cnr1), Faah and Magl mRNA levels were prominently decreased in right prefrontal cortex of FSL rats as compared to FRL rats. Protein expression of CB1R and FAAH were decreased in left hippocampus. In summary, our data suggest a decreased eCB signalling in the FSL rats, which could contribute to the depressive-like behaviour. Interestingly, the altered eCB system activity appear to be hemisphere-specific in the limbic regions. Our study support the existing literature and showed altered eCB system activity in this particular animal model of depression.


Asunto(s)
Depresión/metabolismo , Endocannabinoides/metabolismo , Hipocampo/metabolismo , Corteza Prefrontal/metabolismo , Animales , Cerebro/metabolismo , Depresión/genética , Masculino , Ratas , Ratas Transgénicas , Especificidad de la Especie
9.
Eur J Pain ; 23(1): 117-123, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-29999203

RESUMEN

BACKGROUND: Visual analgesia refers to the phenomena where people report decreased pain intensity when they see the painful or painfully stimulated body part. Alongside pain, sensorimotor impairment (i.e., disturbed proprioception) is also evident in chronic pain. This study aims to investigate whether real-time visual feedback offers additional pain relief and proprioceptive improvement when used in combination with recommended therapies in neck pain patients who received manual therapy with or without real-time visual feedback. METHODS: A total of 29 neck pain patients were recruited in an outpatient physical therapy practice. Patients were randomly allocated to receive manual therapy of the cervical spine with real-time visual feedback or to a control group where patients received manual therapy without real-time visual feedback. Habitual pain intensity, the pressure pain threshold at the zygapophyseal joint of C2-C3 and the superior angle of the scapulae and cervical proprioception were assessed before and immediately after the intervention by a blinded assessor. RESULTS: A between-group comparison revealed a significant reduction in habitual pain in the real-time visual feedback group. No differences were found for the pressure pain threshold or proprioceptive performance. CONCLUSIONS: Real-time visual feedback combined with manual therapy enhanced the analgesic effect of manual therapy in neck pain patients, but had no positive effect on the pressure pain threshold and cervical joint position sense. The technical demands for integrating real-time visual feedback into daily practice to reduce habitual pain are low, have low costs and are easy to apply. SIGNIFICANCE: Real-time visual feedback reduces habitual pain immediately after the intervention. Due to its easy integration, it may be an effective adjunct to recommended interventions (i.e., manual therapy) in patients with neck pain.


Asunto(s)
Dolor Crónico/terapia , Retroalimentación Sensorial , Manipulaciones Musculoesqueléticas , Dolor de Cuello/terapia , Cuello , Propiocepción , Adulto , Dolor Crónico/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dolor de Cuello/fisiopatología , Manejo del Dolor , Dimensión del Dolor , Umbral del Dolor , Modalidades de Fisioterapia , Articulación Cigapofisaria
10.
Chirurg ; 89(12): 1009-1012, 2018 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-30054641

RESUMEN

Work-life balance is a commonly used term that appears in different contexts and has a different meaning for many colleagues. Unfortunately, however, it is often used as a negative, simplified term to describe the assumed attitude of young surgeons towards work and a medical career, even though this is not universally applicable. As the representatives for Young Surgeons of the German Society of Surgery the aim of this article is to present our thoughts on the issue and associated problems and provide a differentiated outline for discussion.


Asunto(s)
Cirujanos , Equilibrio entre Vida Personal y Laboral
11.
Radiat Prot Dosimetry ; 180(1-4): 319-323, 2018 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-29190389

RESUMEN

Bonner sphere measurements are typically analyzed using unfolding codes. It is well known that it is difficult to get reliable estimates of uncertainties for standard unfolding procedures. An alternative approach is to analyze the data using Bayesian parameter estimation. This method provides reliable estimates of the uncertainties of neutron spectra leading to rigorous estimates of uncertainties of the dose. We extend previous Bayesian approaches and apply the method to stray neutrons in proton therapy environments by introducing a new parameterized model which describes the main features of the expected neutron spectra. The parameterization is based on information that is available from measurements and detailed Monte Carlo simulations. The validity of this approach has been validated with results of an experiment using Bonner spheres carried out at the experimental hall of the OncoRay proton therapy facility in Dresden.


Asunto(s)
Teorema de Bayes , Método de Montecarlo , Neutrones , Terapia de Protones , Radiometría/métodos , Dosificación Radioterapéutica , Incertidumbre
12.
Nucl Med Biol ; 52: 63-69, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28648984

RESUMEN

The endocannabinoid system participates in many processes in the body, including memory, reward, pain, motor activity, food intake, energy metabolism, and gastrointestinal functions. [18F]MK-9470 is a positron emission tomography (PET) ligand that binds with high affinity and selectivity to the cannabinoid type 1 receptor. In order to fully characterize ligand behavior, tracer uptake measured using in vivo microPET was compared with results from ex vivo tissue dissection. Twelve male Sprague-Dawley rats were divided into three subgroups and scanned over time periods of 10min, 30min and 90min using PET. Afterwards, a number of the animals' organs were dissected. Uptake of radioactivity was expressed in terms of %ID/ml and %ID/(g tissue). For comparison of in vivo and ex vivo methods, Bland-Altman plots were computed. The highest uptake of [18F]MK-9470 was found in the liver and small intestine; the brain showed less uptake, while low and unspecific binding was observed in tissue of the heart, lung, kidney and bone. In the brain, normalized uptake of [18F]MK-9470 was on average 0.25%ID/ml (range: 0.16 to 0.28%ID/ml). Bland-Altman plots revealed the best agreement between methods for the 90min acquisition protocols. High hepatic accumulation and metabolism of [18F]MK-9470 occur with mainly enteral excretion, which may vary considerably over time - a finding which may be of relevance in metabolite determination in quantitative brain studies. Comparisons between in vivo and ex vivo methods showed that whole-body distribution of [18F]MK-9470 using positron emission tomography is a preferable alternative to ex vivo biodistribution, and requires a significantly smaller number of animals.


Asunto(s)
Piridinas/farmacocinética , Receptor Cannabinoide CB1/metabolismo , Animales , Ligandos , Masculino , Tomografía de Emisión de Positrones , Piridinas/metabolismo , Ratas , Ratas Sprague-Dawley , Distribución Tisular
13.
Neuropharmacology ; 117: 273-281, 2017 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-28219717

RESUMEN

Δ9-Tetrahydrocannabinol (THC) is the psychoactive component of the plant Cannabis sativa and acts as a partial agonist at cannabinoid type 1 and type 2 receptors in the brain. The goal of this study was to assess the effect of THC on the cerebral glucose uptake in the rat brain. 21 male Sprague Dawley rats (12-13 w) were examined and received five different doses of THC ranging from 0.01 to 1 mg/kg. For data acquisition a Focus 120 small animal PET scanner was used and 24.1-28.0 MBq of [18F]-fluoro-2-deoxy-d-glucose were injected. The data were acquired for 70 min and arterial blood samples were collected throughout the scan. THC, THC-OH and THC-COOH were determined at 55 min p.i. Nine volumes of interest were defined, and the cerebral glucose uptake was calculated for each brain region. Low blood THC levels of < 1 ng/ml (injected dose: ≤ 0.01 mg/kg) corresponded to an increased glucose uptake (6-30 %), particularly in the hypothalamus (p = 0.007), while blood THC levels > 10 ng/ml (injected dose: ≥ 0.05 mg/kg) coincided with a decreased glucose uptake (-2 to -22 %), especially in the cerebellar cortex (p = 0.008). The effective concentration in this region was estimated 2.4 ng/ml. This glucose PET study showed that stimulation of CB1 receptors by THC affects the glucose uptake in the rat brain, whereby the effect of THC is regionally different and dependent on dose - an effect that may be of relevance in behavioural studies.


Asunto(s)
Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Agonistas de Receptores de Cannabinoides/farmacología , Dronabinol/farmacología , Glucosa/metabolismo , Psicotrópicos/farmacología , Animales , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Agonistas de Receptores de Cannabinoides/sangre , Agonistas de Receptores de Cannabinoides/farmacocinética , Cromatografía Liquida , Relación Dosis-Respuesta a Droga , Dronabinol/sangre , Dronabinol/farmacocinética , Fluorodesoxiglucosa F18 , Masculino , Tomografía de Emisión de Positrones , Psicotrópicos/sangre , Psicotrópicos/farmacocinética , Radiofármacos , Ratas Sprague-Dawley , Espectrometría de Masas en Tándem
15.
Mol Psychiatry ; 22(10): 1422-1430, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-27698427

RESUMEN

The brain circuits underlying behavioral fear have been extensively studied over the last decades. Although the vast majority of experimental studies assess fear as a transient state of apprehension in response to a discrete threat, such phasic states of fear can shift to a sustained anxious apprehension, particularly in face of diffuse cues with unpredictable environmental contingencies. Unpredictability, in turn, is considered an important variable contributing to anxiety disorders. The networks of the extended amygdala have been suggested keys to the control of phasic and sustained states of fear, although the underlying synaptic pathways and mechanisms remain poorly understood. Here, we show that the endocannabinoid system acting in synaptic circuits of the extended amygdala can explain the fear response profile during exposure to unpredictable threat. Using fear training with predictable or unpredictable cues in mice, combined with local and cell-type-specific deficiency and rescue of cannabinoid type 1 (CB1) receptors, we found that presynaptic CB1 receptors on distinct amygdala projections to bed nucleus of the stria terminalis (BNST) are both necessary and sufficient for the shift from phasic to sustained fear in response to an unpredictable threat. These results thereby identify the causal role of a defined protein in a distinct brain pathway for the temporal development of a sustained state of anxious apprehension during unpredictability of environmental influences, reminiscent of anxiety symptoms in humans.


Asunto(s)
Miedo/fisiología , Receptor Cannabinoide CB1/metabolismo , Amígdala del Cerebelo/metabolismo , Amígdala del Cerebelo/fisiología , Animales , Ansiedad/etiología , Trastornos de Ansiedad/etiología , Trastornos de Ansiedad/metabolismo , Cannabinoides/metabolismo , Cannabinoides/farmacología , Señales (Psicología) , Endocannabinoides/metabolismo , Masculino , Ratones , Receptor Cannabinoide CB1/fisiología , Reflejo de Sobresalto/fisiología , Núcleos Septales/fisiología
16.
Chirurg ; 87(10): 839-46, 2016 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-27484826

RESUMEN

Spinal infections are relatively rare entities but the incidence is significantly increasing due to the rapidly growing numbers of interventions on the spine. Primary infections of intervertebral discs (spondylodiscitis) and vertebral bodies (spondylitis) are distinguished from secondary postinterventional infections. Treatment relies primarily on either conservative or surgical management. In the absence of indications for surgery, a conservative approach is indicated when the patient is neurologically intact and the bony destruction is minimal. Conservative therapeutic options are based on the microbiological diagnosis and use of antibiotics, immobilization, analgesics and orthotics. Indications for a surgical intervention are the presence of neurological deficits, intraspinal abscesses, extensive osseous destruction and failure of conservative management. Surgical therapy focusses on the decompression of neural structures, debridement and eradication of the focus of infection, pathogen identification, correction of the deformity and restoration of a physiological spinal profile. Following a postoperative infection a timely diagnosis including assessment of the extent of infection is crucial. In the case of a purely superficial infection, antibiotic prophylaxis and close monitoring is indicated. If findings are pronounced surgical revision, debridement together with antibiotic therapy and if necessary vacuum-assisted closure as well as revision ranging from exchange of implants to complete removal of osteosynthetic material are required. Spinal infections are severe conditions frequently with residual long-term sequelae, whether the patients are managed conservatively or surgically.


Asunto(s)
Discitis/terapia , Espondilitis/diagnóstico , Espondilitis/terapia , Algoritmos , Antibacterianos/uso terapéutico , Terapia Combinada , Tratamiento Conservador , Desbridamiento , Descompresión Quirúrgica , Discitis/diagnóstico , Discectomía , Humanos , Terapia de Presión Negativa para Heridas , Fusión Vertebral
17.
Z Orthop Unfall ; 154(4): 377-84, 2016 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-27249047

RESUMEN

Periacetabular osteolysis is a frequent long-term complication of cementless total hip arthroplasty. The decision whether to retain or to revise a cup in the presence of osteolysis remains a challenge. The options are regular clinical and radiological check-ups, isolated liner exchange with and without bone grafting, and complete cup revision. Thorough preoperative diagnostics, including a medical history, examination and imaging, are mandatory for correct decision making. In most patients, computed tomography is useful to assess periacetabular osteolysis. If the cup is well-fixed and positioned in an asymptomatic patient without progressive osteolysis and no implant defect or higher grade polyethylene wear and no signs of infection, continuous clinical and radiological monitoring is preferred. If imaging reveals cup loosening, malposition, osteolysis localised in a weight-bearing area, imminent or present periprosthetic fractures, rapid progressive osteolysis, implant defects or massive inlay wear, surgical treatment may be preferred. Cup revision is usually performed in such patients. If the cup is well-positioned and well-fixed in the X-ray, the procedure has to be discussed with the patient individually. Apart from patient-specific risk factors, the risk of further progression has to be assessed. Isolated liner exchange can be performed if the patient is asymptomatic and the cup proves to be stable intraoperatively. It is still unclear whether filling osteolyses through screw holes or osseous windows is of long-term benefit.


Asunto(s)
Acetábulo/cirugía , Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Cadera/métodos , Osteólisis/etiología , Osteólisis/cirugía , Reoperación/métodos , Acetábulo/diagnóstico por imagen , Artroplastia de Reemplazo de Cadera/instrumentación , Medicina Basada en la Evidencia , Humanos , Osteólisis/diagnóstico , Reoperación/instrumentación , Resultado del Tratamiento
18.
Anal Methods ; 8(14): 2880-2886, 2016 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-37457919

RESUMEN

Sample preparation, including bacterial lysis, remains a hurdle in the realization of complete point-of-care tests for many pathogens. Here, we developed a sample preparation methodology for enzymatic lysis and sample heating for low-resource, point-of-care applications. We show an instrument-free chemical heater system for rapid lysis of a gram-positive bacterium (Staphylococcus aureus) and an RNA virus (human respiratory syncytial virus) using a dried lysis enzyme mixture (achromopeptidase) for S. aureus. After a lysis step (<1 minute), lysis enzymes are heat deactivated (<5 minutes) using a simple disposable chemical heater. We demonstrated that both DNA and RNA in the heat-treated sample could be directly amplified without purification, even in the presence of a clinically-obtained human nasal sample. This simple approach to dry enzyme storage and sample heating is adaptable to many applications where samples need to be lysed, including use in low-resource laboratories and in single-use or cartridge-based point-of-care diagnostic devices.

19.
Eur J Vasc Endovasc Surg ; 50(6): 745-53, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26346005

RESUMEN

OBJECTIVES: The aim of the study was to evaluate the potential role of chemokine receptor CXCR4 and its ligand CXCL12 in the pathogenesis of abdominal aortic aneurysm (AAA). METHODS: AAA tissue specimens were obtained from the anterior or lateral aneurysm sac of patients (n = 32, 26 males, 6 females; 66.8 ± 11.2 years, diameter 64.4 ± 17.0 mm), who underwent elective open surgical repair. Twelve non-aneurysmal aortic specimens from transplant donors served as controls. Expression analysis of CXCR4 and CXCL12 at mRNA and protein level was determined by quantitative reverse transcription-polymerase chain reaction (RT-PCR) and western blot. Immunohistochemical staining of corresponding histological sections for CD3 (T-cells), CD20 (B-cells), and CD68 (macrophages) was performed to determine the cellular localization of CXCR4 and CXCL12. Data were analyzed with SPSS 20.0 using Mann-Whitney U test and Spearman's rank correlation coefficient. RESULTS: Gene expression of CXCR4 and CXCL12 was 9.6 and 4.6 fold higher in AAA than in non-aneurysmal aorta (p = .0004 and p < .0001, respectively). Likewise, the protein level of CXCR4 was increased 3.2 fold in AAA wall compared with non-aneurysmal aortic tissue (p < .0001), although CXCL12 could not be detected. Immunohistochemical analysis revealed that CXCR4 was expressed in B and T lymphocytes and macrophages, and CXCL12 was observed only in plasma cells. CONCLUSIONS: This study confirmed the over expression of CXCR4 in human AAA tissue. CXCR4 was detected both at the mRNA and the protein level and by immunohistochemistry, especially in inflammatory cells. In contrast, CXCL12 expression was observed only at the mRNA level, with the exception of plasma cells. The exact role of CXCR4/CXCL12 in AAA has to be further elucidated.


Asunto(s)
Aorta Abdominal/química , Aneurisma de la Aorta Abdominal/metabolismo , Mediadores de Inflamación/análisis , Receptores CXCR4/análisis , Adulto , Anciano , Anciano de 80 o más Años , Aorta Abdominal/diagnóstico por imagen , Aorta Abdominal/cirugía , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/genética , Aneurisma de la Aorta Abdominal/cirugía , Aortografía/métodos , Biomarcadores/análisis , Western Blotting , Estudios de Casos y Controles , Quimiocina CXCL12/análisis , Quimiocina CXCL12/genética , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores CXCR4/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Tomografía Computarizada por Rayos X , Regulación hacia Arriba
20.
Lab Chip ; 15(12): 2647-59, 2015 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-25989457

RESUMEN

The emergence of rapid, user-friendly, point-of-care (POC) diagnostic systems is paving the way for better disease diagnosis and control. Lately, there has been a strong emphasis on developing molecular-based diagnostics due to their potential for greatly increased sensitivity and specificity. One of the most critical steps in developing practical diagnostic systems is the ability to perform sample preparation, especially the purification of nucleic acids (NA), at the POC. As such, we have developed a simple-to-use, inexpensive, and disposable sample preparation system for in-membrane purification and concentration of NAs. This system couples lateral flow in a porous membrane with chitosan, a linear polysaccharide that captures NAs via anion exchange chromatography. The system can also substantially concentrate the NAs. The combination of these capabilities can be used on a wide range of sample types, which are prepared for use in downstream processes, such as qPCR, without further purification.


Asunto(s)
ADN/aislamiento & purificación , Membranas Artificiales , Técnicas Analíticas Microfluídicas/métodos , Sistemas de Atención de Punto , Quitosano , ADN/análisis , ADN/química , Humanos , Porosidad
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