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1.
Nanomaterials (Basel) ; 13(23)2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-38063679

RESUMO

Self-healing nanocomposites can be generated by organic functionalization of inorganic nanoparticles and complementary functionalization of the polymer matrix, allowing reversible interactions between the two components. Here, we report on self-healing nanocomposites based on ionic interactions between anionic copolymers consisting of di(ethylene glycol) methyl ether methacrylate, sodium 4-(methacryloyloxy)butan-1-sulfonate, and cationically functionalized iron oxide nanoparticles. The materials exhibited hygroscopic behavior. At water contents < 6%, the shear modulus was reduced by up to 90%. The nanoparticle concentration was identified as a second factor strongly influencing the mechanical properties of the materials. Backscattered scanning electron microscopy and small-angle X-ray scattering measurements showed the formation of agglomerates in the size range of 100 nm to a few µm in diameter, independent of concentration, resulting in the disordering of the semi-crystalline ionic polymer blocks. These effects resulted in an increase in the shear modulus of the composite from 3.7 MPa to 5.6 MPa, 6.3 Mpa, and 7.5 MPa for 2, 10, and 20 wt% particles, respectively. Temperature-induced self-healing was possible for all composites investigated. However, only 36% of the maximum stress could be recovered in systems with a low nanoparticle content, whereas the original properties were largely restored (>85%) at higher particle contents.

2.
J Breath Res ; 18(1)2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38096565

RESUMO

Due to the overall low abundance of volatile compounds in exhaled breath, it is necessary to preconcentrate the sample prior to traditional thermal desorption (TD) gas chromatography mass spectrometry analysis. While certain aspects of TD tubes, such as volatile storage, have been evaluated, many aspects remain uncharacterized. Two common TD tubes, Tenax TA and Biomonitoring 5TD tubes, were evaluated for background content and flow rate variability. The data illustrate that the Biomonitoring 5TD tubes have the highest number (23) and abundance of background contamination greater than 3x the mean noise when compared to Tenax TA (13) and empty tubes (9). Tentative identifications of the compounds in the background contamination experiment show that greater than 59% (16/27) of the compounds identified have been reported in the breath literature. The data illustrate the TD tube background abundance could account for more than 70% of the chromatographic signal from exhaled breath for these select compounds. Flow rate measurements of 200 Tenax TA and 200 Biomonitoring 5TD tubes show a large range in measured flow rates among the TD tubes (Tenax: 252.9-284.0 ml min-1, 5TD: 220.6-255.1 ml min-1). Finally, TD tubes of each type, Tenax TA and Biomonitoring 5TD, previously established to have high, medium, and low flow rates, show insignificant differences (p> 0.05) among the tubes of different flow rates, using both gas standards and an exhaled breath from a peppermint experiment. Collectively, these results establish overall background compounds attributed to each TD tube type tested. Additionally, while measured flow rate variability is present and plausibly impacts exhaled breath results, the data demonstrate no statistically significant difference was observed between tubes showing high, medium, and low flow rates from two separate sample types.


Assuntos
Compostos Orgânicos Voláteis , Humanos , Compostos Orgânicos Voláteis/análise , Testes Respiratórios/métodos , Expiração , Cromatografia Gasosa-Espectrometria de Massas/métodos , Padrões de Referência
3.
Children (Basel) ; 10(11)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-38002856

RESUMO

The experiences children have in the interactions with their caregivers influence their developmental outcomes. To target caregiving and optimize intervention effects, the assessment of caregiver-child interactions is highly relevant for families affected by parental mental disorders. Behavioral observation is a widely used method for assessing family dynamics, and the literature offers a wide variety of instruments with which to code such data. However, a structured overview of behavioral observation instruments (BOIs) is lacking, and the multitude of types of dyadic behaviors (DBs) assessed within each BOI are complicating their application. We aim to provide an overview of the BOIs applied to families affected by mental disorders and suggest a DB taxonomy that may be used across BOIs. We first conducted a systemic literature search to identify the most frequently used BOIs and the DBs they capture in clinical psychology. Second, we asked 13 experts to sort DB terms based on perceived conceptual similarity and analyzed these results using multidimensional scaling. We found approximately 450 different terms for DBs, and we argue that DBs can be classified within two overarching dimensions, i.e., in terms of structure and in terms of reaction to a child's signals. These efforts can facilitate the coding and application of BOIs in clinical practice.

4.
J Breath Res ; 17(3)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37352843

RESUMO

Exhaled breath research has been hindered by a lack of standardization in collection and analysis methodologies. Recently, the Respiration Collector forIn VitroAnalysis (ReCIVA) sampling device has illustrated the potential to provide a consistent and convenient method for exhaled breath collection onto adsorbent media. However, the significant costs, compared to exhaled breath bags, associated with the standardized collector is believed to be the reason for limited widespread use by researchers in the exhaled breath field. For example, in addition to the sampling hardware, a single-use disposable silicon mask affixed with a filter is required for each exhaled breath collection. To reduce the financial burden, streamline device upkeep, reduce waste material, and ease the logistical burden associated with the single use masks, it is hypothesized that the consumable masks and filters could be sterilized by autoclaving for reuse. The masks were contaminated, autoclaved, and then tested for any surviving pathogens with spore strip standards and by measuring the optical density of cultures. The compound background collected when using the ReCIVA with new masks was compared to that collected with repeatedly autoclaved masks via thermal desorption gas chromatography mass spectrometry (TD-GC-MS). The capacity to block particulate matter of new filters was tested against that of autoclaved filters by introducing an aerosol and comparing pre-filter and post-filter particle counts. Finally, breath samplings were conducted with new masks and autoclaved masks to test for changes in measurements by TD-GC-MS of exogenous and endogenous compounds. The data illustrate the autoclave cycle sterilizes masks spiked with saliva to background levels (p= 0.2527). The results indicate that background levels of siloxane compounds are increased as masks are repetitively autoclaved. The data show that mask filters have significant breakthrough of 1µm particles after five repetitive autoclaving cycles compared to new filters (p= 0.0219). Finally, exhaled breath results utilizing a peppermint ingestion protocol indicate two compounds associated with peppermint, menthone and 1-Methyl-4-(1-methylethyl)-cyclohexanol, and an endogenous exhaled breath compound, isoprene, show no significant difference if sampled with a new mask or a mask autoclaved five times (p> 0.1063). Collectively, the data indicate that ReCIVA masks and filters can be sterilized via autoclave and reused. The results suggest ReCIVA mask and filter reuse should be limited to three times to limit potentially problematic background contaminants and filter dysfunction.


Assuntos
Testes Respiratórios , Esterilização , Humanos , Testes Respiratórios/métodos , Cromatografia Gasosa-Espectrometria de Massas , Expiração , Padrões de Referência
5.
Neurol Res Pract ; 5(1): 7, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36793109

RESUMO

BACKGROUND: Post-stroke dysphagia (PSD) is common and can lead to serious complications. Pharyngeal sensory impairment is assumed to contribute to PSD. The aim of this study was to investigate the relationship between PSD and pharyngeal hypesthesia and to compare different assessment methods for pharyngeal sensation. METHODS: In this prospective observational study, fifty-seven stroke patients were examined in the acute stage of the disease using Flexible Endoscopic Evaluation of Swallowing (FEES). The Fiberoptic Endoscopic Dysphagia Severity Scale (FEDSS) and impaired secretion management according to the Murray-Secretion Scale were determined, as well as premature bolus spillage, pharyngeal residue and delayed or absent swallowing reflex. A multimodal sensory assessment was performed, including touch-technique and a previously established FEES-based swallowing provocation test with different volumes of liquid to determine the latency of swallowing response (FEES-LSR-Test). Predictors of FEDSS, Murray-Secretion Scale, premature bolus spillage, pharyngeal residue, and delayed or absent swallowing reflex were examined with ordinal logistic regression analyses. RESULTS: Sensory impairment using the touch-technique and the FEES-LSR-Test were independent predictors of higher FEDSS, Murray-Secretion Scale, and delayed or absent swallowing reflex. Decreased sensitivity according to the touch-technique correlated with the FEES-LSR-Test at 0.3 ml and 0.4 ml, but not at 0.2 ml and 0.5 ml trigger volumes. CONCLUSIONS: Pharyngeal hypesthesia is a crucial factor in the development of PSD, leading to impaired secretion management and delayed or absent swallowing reflex. It can be investigated using both the touch-technique and the FEES-LSR-Test. In the latter procedure, trigger volumes of 0.4 ml are particularly suitable.

6.
ACS Chem Biol ; 18(2): 230-236, 2023 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-36693632

RESUMO

Transcription-activator-like effectors (TALEs) are programmable DNA binding proteins that can be used for sequence-specific, imaging-based analysis of cellular 5-methylcytosine. However, this has so far been limited to highly repetitive satellite DNA. To expand this approach to the analysis of coding single gene loci, we here explore a number of signal amplification strategies for increasing imaging sensitivity with TALEs. We develop a straightforward amplification protocol and employ it to target the MUC4 gene, which features only a small cluster of repeat sequences. This offers high sensitivity imaging of MUC4, and in costaining experiments with pairs of one TALE selective for unmethylated cytosine and one universal control TALE enables analyzing methylation changes in the target independently of changes in target accessibility. These advancements offer prospects for 5-methylcytosine analysis at coding, nonrepetitive gene loci by the use of designed TALE probe collections.


Assuntos
5-Metilcitosina , Efetores Semelhantes a Ativadores de Transcrição , Efetores Semelhantes a Ativadores de Transcrição/genética , 5-Metilcitosina/metabolismo , DNA/genética , DNA/metabolismo , Sequências Repetitivas de Ácido Nucleico , Proteínas de Ligação a DNA/metabolismo
7.
ACS Sens ; 8(2): 610-618, 2023 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-36657059

RESUMO

Inhaled medications are commonplace for administering bronchodilators, anticholinergics, and corticosteroids. While they have a defined legitimate use, they are also used in sporting events as performance-enhancing drugs. These performance enhancers can be acquired via both legal (i.e., at a pharmacy through over-the-counter medications or through a prescription) and illicit (i.e., black market and foreign pharmacies) means, thus making monitoring procurement impossible. While urine tests can detect these pharmacological agents hours after they have been inhaled, there is a significant lag time before they are observed in urine. Direct detection of these inhaled agents is complicated and requires a multiplexed approach due to the sheer number of inhaled pharmacological agents. Therefore, detection of propellants, which carry the drug into the lungs, provides a simpler path forward toward detection of broad pharmacological agents. In this paper, we demonstrate the first use of terahertz spectroscopy (THz) to detect inhaled medications in human subjects. Notably, we were able to detect and quantitate the propellant, HFA-134a, in breath up to 30 min after using an asthma inhaler, enabling the use of a point-of-care device to monitor exhaled breath for the presence of propellants. We also demonstrate via simulations that the same approach can be leveraged to detect and identify next-generation propellants, specifically HFA-152a. As a result, we provide evidence that a single point-of-care THz sensor can detect when individuals have used pressure-mediated dose inhalers (pMDIs) without further modification of the hardware.


Assuntos
Asma , Espectroscopia Terahertz , Humanos , Propelentes de Aerossol/uso terapêutico , Asma/tratamento farmacológico , Nebulizadores e Vaporizadores , Broncodilatadores/química , Broncodilatadores/uso terapêutico
8.
J Breath Res ; 17(2)2023 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-36596256

RESUMO

Isoprene is one of the most abundant and most frequently evaluated volatile organic compounds in exhaled breath. Recently, several individuals with background levels of exhaled isoprene have been identified. Here, case study data are provided for an individual, identified from a previous study, with this low prevalence phenotype. It is hypothesized that the individual will illustrate low levels of exhaled isoprene at rest and during exercise. At rest, the subject (7.1 ppb) shows background (µ= 14.2 ± 7.0 ppb) levels of exhaled isoprene while the control group illustrates significantly higher quantities (µ= 266.2 ± 72.3 ppb) via proton transfer reaction mass spectrometry (PTR-MS). The result, background levels of isoprene at rest, is verified by thermal desorption gas chromatography mass spectrometry (TD-GC-MS) collections with the individual showing -3.6 ppb exhaled isoprene while the room background containedµ= -4.1 ± 0.1 ppb isoprene. As isoprene has been shown previously to increase at the initiation of exercise, exercise bike experiments were performed with the individual identified with low isoprene, yielding low and invariant levels of exhaled isoprene (µ= 6.6 ± 0.1 ppb) during the exercise while control subjects illustrated an approximate 2.5-fold increase (preµ= 286.3 ± 43.8 ppb, exerciseµ= 573.0 ± 147.8 ppb) in exhaled isoprene upon exercise start. Additionally, exhaled breath bag data showed a significant decrease in isoprene (delta post/pre, p = 0.0078) of the control group following the exercise regimen. Finally, TD-GC-MS results for exhaled isoprene from the individual's family (mother, father, sister and maternal grandmother) illustrated that the mother and father exhibited isoprene values (28.5 ppb, 77.2 ppb) below control samples 95% confidence interval (µ= 166.8 ± 43.3 ppb) while the individual's sister (182.0 ppb) was within the control range. These data provide evidence for a large dynamic range in exhaled isoprene in this family. Collectively, these results provide additional data surrounding the existence of a small population of individuals with background levels of exhaled isoprene.


Assuntos
Testes Respiratórios , Butadienos , Testes Respiratórios/métodos , Espectrometria de Massas/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Butadienos/análise , Hemiterpenos/análise , Expiração
9.
In Vivo ; 36(5): 2042-2051, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36099106

RESUMO

BACKGROUND/AIM: Macrophages and biomaterial-induced multinucleated giant cells (BMGCs) are central elements in the tissue reaction cascade towards bone substitute materials (BSM). The enzymatic detection of the lytic enzyme tartrate-resistant acid phosphatase (TRAP) has manifoldly been used to examine the so-called "bioactivity" of BSM. The present study aimed to compare the detection validity and expression pattern of the TRAP enzyme using enzymatic and immunohistochemical detection methods in the context of biocompatibility analyses of BSM. PATIENTS AND METHODS: Biopsies from 8 patients were analyzed after sinus augmentation with a xenogeneic bone substitute. Analysis of both macrophage and BMGC polarization were performed by histochemical TRAP detection and immunohistochemical detection of TRAP5a. Histomorphometrical analysis was used for comparison of the TRAP detection of BMGCs. RESULTS: The enzymatic TRAP detection method revealed that in 7 out of 8 biopsies only single cells were TRAP-positive, whereas most of the cells and especially the BMGCs were TRAP-negative. The immunohistochemical detection of TRAP5a showed moderate numbers of stained mononuclear cells, while the majority of the BMGCs showed signs of TRAP5a-expression. The enzymatic TRAP detection was comparable to the results obtained via immunohistochemistry only in one case. The histomorphometrical analysis showed that significantly more mononuclear and multinucleated TRAP-positive cells were found using immunohistochemical TRAP5a-staining compared to the enzymatic TRAP detection method. Also, significantly more TRAP-negative BMGCs were found using the enzymatic TRAP detection. CONCLUSION: The immunohistochemical detection of TRAP is more accurate for examination of the bioactivity and cellular degradability of BSM.


Assuntos
Substitutos Ósseos , Fosfatase Ácida/análise , Fosfatase Ácida/metabolismo , Materiais Biocompatíveis , Humanos , Imuno-Histoquímica , Fosfatase Ácida Resistente a Tartarato
11.
Lancet Psychiatry ; 9(8): 676-688, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35750060

RESUMO

Integrating HIV-related care with treatment for substance use disorder provides an opportunity to better meet the needs of people living with these conditions. People with substance use disorder are rendered especially vulnerable by prevailing policies, structural inequalities, and stigmatisation. In this Series paper we analyse existing literature and empirical evidence from scoping reviews on integration designs for the treatment of HIV and substance use disorder, to understand barriers to and facilitators of care integration and to map ways forward. We discuss how approaches to integration address two core gaps in current models: a failure to consider human rights when incorporating the perspectives of people living with HIV and people who use drugs, and a failure to reflect critically on structural factors that determine risk, vulnerability, health-care seeking, and health equity. We argue that successful integration requires a person-centred approach, which is grounded in human rights, treats both concerns holistically, and reconnects with underlying social, economic, and political inequalities.


Assuntos
Infecções por HIV , Transtornos Relacionados ao Uso de Substâncias , Infecções por HIV/terapia , Direitos Humanos , Humanos , Transtornos Relacionados ao Uso de Substâncias/terapia
12.
Clin Oral Investig ; 26(8): 5261-5272, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35593928

RESUMO

OBJECTIVES: The present randomized controlled clinical study aimed to investigate if, in lateral maxillary sinus augmentation, the repositioned bony wall or the application of a collagen membrane results in more preferable new hard tissue formation. MATERIALS AND METHODS: Forty patients were divided into two study groups. Both groups received a xenogeneic bone substitute material (BSM) during lateral sinus augmentation. In the bony wall group (BW), following piezosurgery, the retrieved bony wall was repositioned. In the collagen membrane group (CM), following rotary instrument preparation, collagen membrane coverage was applied. After 6 months, biopsies were taken to histologically analyze the percentage of BSM, connective tissue (CT), and newly formed bone (NFB) following both approaches. RESULTS: Forty implants were placed and 29 harvested biopsies could be evaluated. Duration of surgery, membrane perforations, and VAS were detected. Histomorphometrical analysis revealed comparable amounts of all analyzed parameters in both groups in descending order: CT (BW: 39.2 ± 9%, CM: 37,9 ± 8.5%) > BSM (BW: 32.9 ± 6.3%, CM: 31.8 ± 8.8%) > NB (BW: 27.8 ± 11.2%, CM: 30.3 ± 4.5%). CONCLUSIONS: The results of the present study show that the closure of the access window by means of the retrieved bony wall or a native collagen membrane led to comparable bone augmentation results. CLINICAL TRIAL: clinicaltrials.gov NCT04811768. CLINICAL RELEVANCE: Lateral maxillary sinus augmentation with the application of a xenogeneic BSM in combination with a native collagen membrane for bony window coverage represents a reliable method for surgical reconstruction of the posterior maxilla. Piezosurgery with bony window repositioning delivers comparable outcomes without membrane coverage.


Assuntos
Substitutos Ósseos , Levantamento do Assoalho do Seio Maxilar , Seios Transversos , Regeneração Óssea , Colágeno , Implantação Dentária Endóssea/métodos , Humanos , Maxila/patologia , Maxila/cirurgia , Seio Maxilar/patologia , Seio Maxilar/cirurgia , Estudos Prospectivos , Levantamento do Assoalho do Seio Maxilar/métodos , Seios Transversos/cirurgia
13.
BMJ Open ; 11(12): e055600, 2021 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-34880027

RESUMO

INTRODUCTION: Recent studies have pointed to the substantial role of private health sector delivery of maternal and newborn health (MNH) care in low-/middle-income countries (LMICs). While this role has been partly documented, an evidence synthesis is missing. To analyse opportunities and challenges of private sector delivery of MNH care as they pertain to the new World Health Organization (WHO) strategy on engaging the private health service delivery sector through governance in mixed health systems, a more granular understanding of the private health sector's role and extent in MNH delivery is imperative. We developed a scoping review protocol to map and conceptualise interventions that were explicitly designed and implemented by formal private health sector providers to deliver MNH care in mixed health systems. METHODS AND ANALYSIS: This protocol details our intended methodological and analytical approach following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for scoping reviews. Seven databases (Cumulative Index to Nursing and Allied Health, Excerpta Medica Database, International Bibliography of the Social Sciences, PubMed, ScienceDirect, Web of Science, WHO Institutional Repository for Information Sharing) and two websites will be searched for studies published between 1 January 2002 and 1 June 2021. For inclusion, quantitative and/or qualitative studies in LMICs must report at least one of the following outcomes: maternal morbidity or mortality; newborn morbidity or mortality; experience of care; use of formal private sector care during pregnancy, childbirth, and postpartum; and stillbirth. Analyses will synthesise the evidence base and gaps on private sector MNH service delivery interventions for each of the six governance behaviours. ETHICS AND DISSEMINATION: Ethical approval is not required. Findings will be used to develop a menu of private sector interventions for MNH care by governance behaviour. This study will be disseminated through a peer-reviewed publication, working groups, webinars and partners.


Assuntos
Serviços de Saúde Materna , Setor Privado , Países em Desenvolvimento , Feminino , Humanos , Renda , Saúde do Lactente , Recém-Nascido , Gravidez , Literatura de Revisão como Assunto , Revisões Sistemáticas como Assunto
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