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A waste product biomass sample was received and charred to produce the biochar sample. The char reactivity experiments were conducted in a high-pressure fixed bed reactor in the temperature range of 700-730 °C. The steam pressure was varied from 1 to 10 bar steam, and the CO and CO2 products were measured and used to determine the specific reaction rate of biochar. The results showed that the reaction rate increased with conversion, temperature and steam partial pressure. The increase in steam partial pressure had a significant effect on the reaction rate up to 10 bar steam, where it was observed that the formation of CO2 contributed more to the specific reaction rate than that of CO and that the selectivity of CO2 increased over the steam pressure range. The use of these kinetic models also determined the activation energy, and the results were found to be consistent with the literature.
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Orbital friction stir welding (FSW) has been applied to clad pipes, which is certainly of interest to the oil and gas industry. In this context, an FSW system capable of performing sound joints in one pass with full tool penetration was developed. Orbital FSW was executed in 6 mm thick API X65 PSL2 steel clad pipes with 3 mm thick Inconel 625 using a polycrystalline cubic boron nitride (pcBN) tool. The metallurgical and mechanical properties of the joints were investigated. Sound joints with axial forces of 45-50 kN, tool rotational speeds of 400-500 rpm, and a welding speed of 2 mm/s were obtained, illustrating that the developed system can perform FSW joints without volumetric defects.
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Soldagem , Estudos de Viabilidade , Fricção , Metalurgia , SomRESUMO
Coordinated changes of cellular plasticity and identity are critical for pluripotent reprogramming and oncogenic transformation. However, the sequences of events that orchestrate these intermingled modifications have never been comparatively dissected. Here, we deconvolute the cellular trajectories of reprogramming (via Oct4/Sox2/Klf4/c-Myc) and transformation (via Ras/c-Myc) at the single-cell resolution and reveal how the two processes intersect before they bifurcate. This approach led us to identify the transcription factor Bcl11b as a broad-range regulator of cell fate changes, as well as a pertinent marker to capture early cellular intermediates that emerge simultaneously during reprogramming and transformation. Multiomics characterization of these intermediates unveiled a c-Myc/Atoh8/Sfrp1 regulatory axis that constrains reprogramming, transformation and transdifferentiation. Mechanistically, we found that Atoh8 restrains cellular plasticity, independent of cellular identity, by binding a specific enhancer network. This study provides insights into the partitioned control of cellular plasticity and identity for both regenerative and cancer biology.
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Reprogramação Celular , Células-Tronco Pluripotentes Induzidas , Plasticidade Celular/genética , Reprogramação Celular/genética , Células-Tronco Pluripotentes Induzidas/metabolismo , Fator 3 de Transcrição de Octâmero/genética , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismoRESUMO
In TAE Technologies' current experimental device, C-2W (also called "Norman"), record-breaking, advanced beam-driven field-reversed configuration plasmas are produced and sustained in steady state utilizing variable energy neutral beams, advanced divertors, edge-biasing electrodes, and an active plasma control system [Gota et al., Nucl. Fusion 61, 106039 (2021)]. A novel diagnostic has been developed by TAE Technologies to leverage an industrial fiber Bragg grating (FBG) sensor array to detect heat flux along the wall of the vacuum vessel from a plasma discharge. The system consists of an optical fiber with FBG sensors distributed along its length, housed in a pressurized steel sheath. Each FBG sensor is constructed to reflect a different wavelength, the exact value of which is sensitive to the strain and temperature at the location of the grating in the fiber. The fiber is illuminated with broadband light, and the data acquisition system analyzes the spectrum of reflected light to determine the temperature at the location of each FBG. We have installed four of these vacuum-rated FBG sensor arrays on the C-2W experiment, each with 30 individual FBG sensors spaced at 0.15 m intervals along the 5 m fiber, with a 100 Hz acquisition rate. The measurement of temperature change due to a plasma discharge provides a single data point at each sensor location, creating a 120-point heat map of the vacuum vessel.
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While the aurora has attracted attention for millennia, important questions remain unanswered. Foremost is how auroral electrons are accelerated before colliding with the ionosphere and producing auroral light. Powerful Alfvén waves are often found traveling Earthward above auroras with sufficient energy to generate auroras, but there has been no direct measurement of the processes by which Alfvén waves transfer their energy to auroral electrons. Here, we show laboratory measurements of the resonant transfer of energy from Alfvén waves to electrons under conditions relevant to the auroral zone. Experiments are performed by launching Alfvén waves and simultaneously recording the electron velocity distribution. Numerical simulations and analytical theory support that the measured energy transfer process produces accelerated electrons capable of reaching auroral energies. The experiments, theory, and simulations demonstrate a clear causal relationship between Alfvén waves and accelerated electrons that directly cause auroras.
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BACKGROUND: Trichomoniasis commonly affects women of childbearing age and has been linked to several adverse birth outcomes. OBJECTIVE: To elucidate the association between trichomoniasis in pregnant women and adverse birth outcomes, including preterm delivery, prelabour rupture of membranes and low birthweight. SEARCH STRATEGY: MEDLINE, EMBASE and ClinicalTrials.gov were systematically searched in December 2020 without time or language restrictions. SELECTION CRITERIA: Original research studies were included if they assessed at least one of the specified adverse birth outcomes in pregnant women with laboratory-diagnosed trichomoniasis. DATA COLLECTION AND ANALYSIS: Estimates from included articles were either extracted or calculated and then pooled to produce a combined estimate of the association of trichomoniasis with each adverse birth outcome using the random effects model. Heterogeneity was assessed using the I2 statistic and Cochran's Q test. MAIN RESULTS: Literature search produced 1658 publications after removal of duplicates (n = 770), with five additional publications identified by hand search. After screening titles and abstracts for relevance, full text of 84 studies was reviewed and 19 met inclusion criteria for meta-analysis. Significant associations were found between trichomoniasis and preterm delivery (OR 1.27; 95% CI 1.08-1.50), prelabour rupture of membranes (OR 1.87; 95% CI 1.53-2.29) and low birthweight (OR 2.12; 95% CI 1.15-3.91). CONCLUSIONS: Trichomoniasis in pregnant women is associated with preterm delivery, prelabour rupture of membranes and low birthweight. Rigorous studies are needed to determine the impact of universal trichomoniasis screening and treatment during pregnancy on reducing perinatal morbidity. TWEETABLE ABSTRACT: This systematic review and meta-analysis found that in the setting of pregnancy, trichomoniasis is significantly associated with multiple adverse birth outcomes, including preterm delivery, low birthweight, and prelabour rupture of membranes.
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Complicações Parasitárias na Gravidez/parasitologia , Resultado da Gravidez , Vaginite por Trichomonas/complicações , Trichomonas vaginalis , Feminino , Ruptura Prematura de Membranas Fetais/parasitologia , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Gravidez , Nascimento Prematuro/parasitologiaRESUMO
BACKGROUND AND OBJECTIVES: Peach gibberellin-regulated protein (peamaclein) has recently emerged as a relevant food allergen in cypress pollen-hypersensitive patients. Objective: We investigated monosensitization to peamaclein among Italian cypress pollen-allergic patients. MATERIAL AND METHODS: A total of 835 cypress pollen-hypersensitive patients from 28 Italian allergy centers underwent a thorough work-up to determine food-allergic reactions and performed skin prick testing with a commercial peach extract containing peamaclein. IgE to rPru p 3 was measured in peach reactors, and those with negative results were enrolled as potentially monosensitized to peamaclein. IgE reactivity to rPru p 7 was evaluated using immunoblot and an experimental ImmunoCAP with rPru p 7. RESULTS: Skin prick tests were positive to peach in 163 patients (19.5%); however, 127 (77.9%) were excluded because they reacted to Pru p 3. Twenty-four patients (14.7%) corresponding to 2.8% of the entire study population) were considered potentially monosensitized to peamaclein. No geographic preference was observed. Seventeen of the 24 patients (70.8%) had a history of food allergy, mainly to peach (n=15). Additional offending foods included other Rosaceae, citrus fruits, fig, melon, tree nuts, and kiwi. On peach immunoblot, only 3 of 18 putative peamaclein-allergic patients reacted to a band at about 7 kDa; an additional 4 patients reacted at about 50-60 kDa. Ten of 18 patients (56%) had a positive result for Pru p 7 on ImmunoCAP. CONCLUSION: Allergy and sensitization to peamaclein seem rare in Italy. Most patients react to peach, although other Rosaceae fruits and several citrus fruits may also be offending foods. Peach and cypress pollen probably also share cross-reacting allergens other than peamaclein.
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Cupressus , Hipersensibilidade Alimentar , Alérgenos/efeitos adversos , Antígenos de Plantas/efeitos adversos , Reações Cruzadas , Hipersensibilidade Alimentar/epidemiologia , Giberelinas , Humanos , Imunoglobulina E , Proteínas de Plantas/efeitos adversos , Pólen , Testes Cutâneos/efeitos adversosRESUMO
This study reports in-situ sedimentologic evidence of giant floods in Gale crater, Mars, during the Noachian Period. Features indicative of floods are a series of symmetrical, 10 m-high gravel ridges that occur in the Hummocky Plains Unit (HPU). Their regular spacing, internal sedimentary structures, and bedload transport of fragments as large as 20 cm suggest that these ridges are antidunes: a type of sedimentary structure that forms under very strong flows. Their 150 m wavelength indicates that the north-flowing water that deposited them was at least 24 m deep and had a minimum velocity of 10 m/s. Floods waned rapidly, eroding antidune crests, and re-deposited removed sediments as patches on the up-flow limbs and trough areas between these ridges forming the Striated Unit (SU). Each patch of the SU is 50-200 m wide and long and consists of 5-10 m of south-dipping layers. The strike and dip of the SU layers mimic the attitude of the flank of the antidune on which they were deposited. The most likely mechanism that generated flood waters of this magnitude on a planet whose present-day average temperature is - 60 °C was the sudden heat produced by a large impact. The event vaporized frozen reservoirs of water and injected large amounts of CO2 and CH4 from their solid phases into the atmosphere. It temporarily interrupted a cold and dry climate and generated a warm and wet period. Torrential rainfall occurred planetwide some of which entered Gale crater and combined with water roaring down from Mt. Sharp to cause gigantic flash floods that deposited the SU and the HPU on Aeolis Palus. The warm and wet climate persisted even after the flooding ended, but its duration cannot be determined by our study.
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Betacoronavirus , Infecções por Coronavirus/complicações , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/complicações , Pneumonia Viral/diagnóstico , Púrpura/patologia , Púrpura/virologia , Vasculite Leucocitoclástica Cutânea/patologia , COVID-19 , Infecções por Coronavirus/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/terapia , Púrpura/terapia , SARS-CoV-2RESUMO
PURPOSE: Prior reports on the location and sizes of brain metastases almost entirely focus on patients with primary breast and pulmonary cancer. This is the first study comparing multiple other types of cancer that metastasize to the brain. METHODS: This monocentric retrospective study includes 369 untreated patients with 3313 intraaxial brain metastases. Following semi-manual segmentation of metastases on post-contrast T1WI, cumulative spatial probability distribution maps of brain metastases were created for the whole group and for all primary tumors. Furthermore, mixed effects logistic regression model analysis was performed to determine if the primary tumor, patient age, and patient sex influence lesion location. RESULTS: The cerebellum as location of brain metastases was proportionally overrepresented. Breast and pulmonary cancer caused higher number of brain metastases to what would normally be expected. Multivariate analyses revealed a significant accumulation of brain metastases from skin cancer in a frontal and from breast and gastrointestinal cancer in a cerebellar location. CONCLUSION: Distribution of brain metastases is very heterogeneous for the distinct primaries, possibly reflecting the diversity of mechanisms involved in brain metastases formation. In daily clinical practice distribution patters may be beneficial to predict the primary cancer site, if unknown.
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Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/secundário , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Metástase Neoplásica/diagnóstico por imagem , Metástase Neoplásica/patologia , Idoso , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/epidemiologia , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Feminino , Neoplasias Gastrointestinais/epidemiologia , Neoplasias Gastrointestinais/patologia , Neoplasias de Cabeça e Pescoço/epidemiologia , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sarcoma/epidemiologia , Sarcoma/patologia , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/patologia , Neoplasias Urogenitais/epidemiologia , Neoplasias Urogenitais/patologiaAssuntos
Alérgenos/efeitos adversos , Anafilaxia/enzimologia , Venenos de Artrópodes/efeitos adversos , Himenópteros/imunologia , Isquemia/enzimologia , Triptases/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anafilaxia/sangue , Animais , Biomarcadores/sangue , Criança , Pré-Escolar , Feminino , Humanos , Isquemia/sangue , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Adulto JovemRESUMO
Meloidogyne aegracyperi n. sp. is described from roots of purple nutsedge in southern New Mexico, USA. Mature females are small (310-460 µm), pearly white, with their egg masses completely contained inside root galls. The neck is often at a 90 to 130° angle to the protruding posterior end with the perineal pattern. The distance of the dorsal esophageal gland orifice (DGO) to the base of the stylet is relatively long (4.0-6.1 µm), and the excretory pore is level with the base of the stylet. The anterior portion of the rounded lumen lining of the metacorpus contains 3 to 10 small vesicles. The perineal pattern has a rounded dorsal arch with a tail terminal area that is smooth or marked with rope-like striae. Only two males were found. The body twists 90° throughout its length. The DGO to the base of the stylet is long (3.0-3.3) µm. The cephalic framework of the second-stage juvenile is weak, and the stylet is short (10.1-11.8 µm). The DGO to the base of the stylet is long (3-5 µm). The tail is very long (64-89 µm) and the hyaline portion of the tail is very narrow, making the tail finely pointed. Eggs are typical for the genus and vary in length (85.2-99.8 µm) and width (37.1-48.1 µm), having a L/W ratio of (2.1-2.6). Maximum likelihood phylogenetic analyses of the different molecular loci (partial 18S rRNA, D2-D3 of 28S rRNA, internal transcribed spacer (ITS) rRNA, cytochrome oxidase subunit II (COII)-16S rRNA of mitochondrial DNA gene fragments and partial Hsp90 gene) placed this nematode on an independent branch in between M. graminicola and M. naasi and a cluster of species containing M. chitwoodi. M. fallax, and M. minor. Greenhouse tests showed that yellow and purple nutsedge were the best hosts, but perennial ryegrass, wheat, bentgrass, and barley were also hosts.
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BACKGROUND: Patients in circulatory shock exhibit insufficient peripheral perfusion to ensure adequate oxygenation of vital organs such as the heart and brain. Early detection of reduced tissue oxygen saturation (StO2) could be used for rapid therapeutic intervention and thus improve the prognosis of patients in the early stage of multiple organ dysfunction syndrome (MODS). MATERIALS AND METHODS: A total of 60 patients in the early stage of MODS (APACHE [Acute Physiology and Chronic Health Evaluation] II score ≥20) were investigated in a monocentric, prospective, randomized phase II study. StO2 was measured using the InSpectraTM StO2 system and compared with known indicators of hypoxia (peripheral oxygen saturation [SpO2], arterial oxygen saturation [SaO2], central venous oxygen saturation [ScvO2], pH, serum lactate). Clinical endpoints of the study were 28-day and 6month mortality as well as the need for invasive mechanical ventilation and renal replacement therapy during the hospital stay, respectively. RESULTS: An increased 28-day and 6month mortality is found for patients with StO2 <75% in contrast to patients with StO2 ≥75%. Correlations of StO2 with SpO2, ScvO2, and serum lactate are confirmed. Patients with reduced StO2 tend to show a higher disease severity as measured by APACHE II score. CONCLUSION: StO2 shows prognostic relevance in patients at the early stage of MODS. Thus, the rapid and noninvasive assessment of StO2 could be useful in risk stratification of these patients.
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Insuficiência de Múltiplos Órgãos , Consumo de Oxigênio , Idoso , Feminino , Humanos , Masculino , Prognóstico , Estudos Prospectivos , Espectroscopia de Luz Próxima ao InfravermelhoRESUMO
Innate lymphoid cells (ILCs) play an important role in regulating immune responses at mucosal surfaces. The transcription factor T-bet is crucial for the function of ILC1s and NCR+ ILC3s and constitutive deletion of T-bet prevents the development of these subsets. Lack of T-bet in the absence of an adaptive immune system causes microbiota-dependent colitis to occur due to aberrant ILC3 responses. Thus, T-bet expression in the innate immune system has been considered to dampen pathogenic immune responses. Here, we show that T-bet plays an unexpected role in negatively regulating innate type 2 responses, in the context of an otherwise intact immune system. Selective loss of T-bet in ILCs leads to the expansion and increased activity of ILC2s, which has a functionally important impact on mucosal immunity, including enhanced protection from Trichinella spiralis infection and inflammatory colitis. Mechanistically, we show that T-bet controls the intestinal ILC pool through regulation of IL-7 receptor signalling. These data demonstrate that T-bet expression in ILCs acts as the key transcriptional checkpoint in regulating pathogenic vs. protective mucosal immune responses, which has significant implications for the understanding of the pathogenesis of inflammatory bowel diseases and intestinal infections.
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Colite/imunologia , Mucosa Intestinal/imunologia , Proteínas com Domínio T/metabolismo , Trichinella spiralis/fisiologia , Triquinelose/imunologia , Animais , Células Cultivadas , Humanos , Imunidade Celular , Imunidade Inata , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Interleucina-7/metabolismo , Transdução de Sinais , Proteínas com Domínio T/genética , Células Th2/imunologiaRESUMO
A 63-year-old man presented with intermittent, progressively worsening dyspnoea associated with cough and blood-tinged sputum. Initial work-up showed left axis deviation on ECG, chest X-ray with an elevated left hemidiaphragm and a non-contrast CT chest that showed a multilobulated mass in the proximal trachea. Bronchoscopy showed a whitish-appearing lesion, which was then sampled and partially resected with pathology showing a schwannoma with no malignant cells. He felt partial relief post procedure; however, he presented a month later with similar symptoms of dyspnoea and a repeat CT scan showed enlargement of the mass in the same location. The patient underwent another flexible bronchoscopy and resection with argon plasma coagulation (APC)/electrocautery snare. APC/electrocautery is an effective interventional bronchoscopy technique that can be used to resect endoluminal lesions or extraluminal lesions that have infiltrated into the airway using flexible/rigid bronchoscopy. It is more cost-effective, safe, works well with vascular lesions and achieves excellent haemostasis as compared with Nd:YAG lasers.
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Coagulação com Plasma de Argônio/métodos , Neurilemoma/patologia , Traqueia/patologia , Neoplasias da Traqueia/patologia , Broncoscopia/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Neurilemoma/diagnóstico por imagem , Neurilemoma/terapia , Traqueia/diagnóstico por imagem , Traqueia/inervação , Traqueia/cirurgia , Neoplasias da Traqueia/diagnóstico por imagem , Neoplasias da Traqueia/terapia , Resultado do TratamentoRESUMO
OBJECTIVE: To identify the determinants of natural cause mortality in a cohort of individuals with serious mental illness assessed prospectively. METHOD: Persons with schizophrenia (n = 789) and bipolar disorder (n = 498), mean age of 38 (s.d. 12.6) years, underwent an in-person clinical assessment. They also had a blood sample drawn from which infectious disease markers were measured. Mortality was subsequently determined utilizing data from the National Death Index following a period of up to 16.9 years. RESULTS: A total of 6.8% (87 of 1287) of persons died of natural causes. Mortality was predicted in a multivariate model by baseline cigarette smoking (RR = 6.29, 95% CI 1.41, 3.72, P = 0.00076); divorced or widowed status (RR = 1.90, CI 1.21, 2.99); reduced cognitive score (RR = 0.73, CI 0.61, 0.87); receipt of antidepressant medication (RR = 1.74, CI 1.12, 2.71); elevated levels of antibodies to Epstein-Barr virus (EBV) (RR = 1.29, CI 1.01, 1.66); and a genitourinary (RR = 1.82, CI 1.16, 2.86), respiratory (RR = 1.82, CI 1.16, 2.86), or cardiac (RR = 2.09, CI 1.33, 3.29) condition. There was an additive effect of smoking and both a cardiac and a respiratory condition but not elevated EBV antibody levels. CONCLUSION: Smoking is a modifiable behaviour which is associated with mortality in this population.
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Transtorno Bipolar/epidemiologia , Causas de Morte , Fumar Cigarros/epidemiologia , Cardiopatias/epidemiologia , Pneumopatias/epidemiologia , Transtornos Psicóticos/epidemiologia , Esquizofrenia/epidemiologia , Adulto , Comorbidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , RiscoRESUMO
How has evolution led to the variation in behavioural phenotypes (personalities) in a population? Knowledge of whether personality is heritable, and to what degree it is influenced by the social environment, is crucial to understanding its evolutionary significance, yet few estimates are available from natural populations. We tracked three behavioural traits during different life-history stages in a pedigreed population of wild house sparrows. Using a quantitative genetic approach, we demonstrated heritability in adult exploration, and in nestling activity after accounting for fixed effects, but not in adult boldness. We did not detect maternal effects on any traits, but we did detect a social brood effect on nestling activity. Boldness, exploration and nestling activity in this population did not form a behavioural syndrome, suggesting that selection could act independently on these behavioural traits in this species, although we found no consistent support for phenotypic selection on these traits. Our work shows that repeatable behaviours can vary in their heritability and that social context influences personality traits. Future efforts could separate whether personality traits differ in heritability because they have served specific functional roles in the evolution of the phenotype or because our concept of personality and the stability of behaviour needs to be revised.
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Comportamento Animal/fisiologia , Pardais/fisiologia , Animais , Personalidade , Característica Quantitativa Herdável , Comportamento Social , Pardais/genéticaRESUMO
AIM: The aim of this study was a comparison of the handling and acceptance of two kinds of interdental brushes (interdental brush with a handle [HB] and a newly invented interdental cleaning device [NB]). METHODS AND MATERIALS: In a randomized crossover trial, 40 test subjects with an average number of 23.5 interdental areas were examined. At two appointments with a "washout" period of one week, the volunteers tried out both cleaning tools (HB and NB). They were asked to clean as many interdental spaces as possible. The percentage of spaces, which could be reached, is the IRI (Interdental Reachability Index). Furthermore, subjective impressions were determined. RESULTS: The average IRI using HB was 64% compared to 80% using of NB (P<.001); 62.5% of the volunteers found the cleaning with HB painful and 15% the cleaning with NB. The subjective feeling after cleaning was 1.75 with NB compared to 2.2 with HB (P=.015), grading the feeling, from 1 for "very good" to 5 for "poor." The acceptance of regular interdental hygiene was rated 1.95 in the case of the NB and 2.85 in the case of the HB. After both appointments, the test subjects declared that they would use the NB 3.05 times and the HB 1.78 times a week. CONCLUSION: This study shows that the test subjects reached more interdental spaces with NB than with the HB. NB can improve the usage of interdental brushes. Regarding subjective comfort, participants also favoured NB over HB.
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Dispositivos para o Cuidado Bucal Domiciliar , Placa Dentária/prevenção & controle , Higiene Bucal/instrumentação , Escovação Dentária/instrumentação , Adulto , Estudos Cross-Over , Desenho de Equipamento , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Allergic inflammation is a common feature of asthma and may contribute to both development and perpetuation of disease. The interaction of antigen-presenting cells (APC) with sensitized helper T lymphocytes (TC) producing Th2 cytokines may determine the inflammatory response. Recruitment of APC and TC to the lung during allergic responses has been demonstrated, but functional studies in humans have been limited. OBJECTIVE: This study examined the function of APC and TC accumulating at sites of inflammation after segmental allergen challenge (SAC). METHODS: Fifteen allergic patients underwent SAC, and cells from bronchoalveolar lavage (BAL) were collected after 24 hours. APC and TC from the blood and BAL were purified based on expression of the monocyte marker, CD14; the plasmacytoid dendritic cell (pDC) marker, BDCA4, identifying neuropilin-1 (NRP1); and the helper T cell marker, CD4. Functional activity was assessed using allergen-induced T cell proliferation. Flow cytometry identified cells expressing CD14 and NRP1. RESULTS: SAC resulted in a 12-fold increase in mononuclear cells having the morphologic appearance of blood monocytes. Most of these cells co-expressed CD14 and NRP1. After saline challenge, BAL mononuclear cells demonstrated little APC function. Following SAC, BAL mononuclear cells showed function equal to pDC from blood and greater than blood monocytes. Purified NRP1+ cells from BAL had even greater function than pDC cells from blood (P = .008). Using consistent sources of APC, enhanced proliferation of TC from lung compared to blood was also demonstrated (P = .002). CONCLUSIONS: The marked increase in APC function for allergen-specific TC proliferation during allergic inflammation is largely due to the recruitment of monocytes and dendritic cells. There is also an enhanced response in the lung TC population, consistent with recruitment of allergen-specific T cells. Interactions between recruited APC and TC may occur as an early event promoting allergic airway inflammation.