Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
Mais filtros

País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Sensors (Basel) ; 17(2)2017 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-28208678

RESUMO

We hypothesize that our smartphone-based fingertip image-based heart rate detection methods reliably detect the heart rhythm and rate of subjects. We propose fingertip curve line movement-based and fingertip image intensity-based detection methods, which both use the movement of successive fingertip images obtained from smartphone cameras. To investigate the performance of the proposed methods, heart rhythm and rate of the proposed methods are compared to those of the conventional method, which is based on average image pixel intensity. Using a smartphone, we collected 120 s pulsatile time series from each recruited subject. The results show that the proposed fingertip curve line movement-based method detects heart rate with a maximum deviation of 0.0832 Hz and 0.124 Hz using time- and frequency-domain based estimation, respectively, compared to the conventional method. Moreover, another proposed fingertip image intensity-based method detects heart rate with a maximum deviation of 0.125 Hz and 0.03 Hz using time- and frequency-based estimation, respectively.


Assuntos
Dedos , Frequência Cardíaca , Humanos , Smartphone
2.
N Engl J Med ; 367(8): 725-34, 2012 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-22913682

RESUMO

BACKGROUND: Autoantibodies against interferon-γ are associated with severe disseminated opportunistic infection, but their importance and prevalence are unknown. METHODS: We enrolled 203 persons from sites in Thailand and Taiwan in five groups: 52 patients with disseminated, rapidly or slowly growing, nontuberculous mycobacterial infection (group 1); 45 patients with another opportunistic infection, with or without nontuberculous mycobacterial infection (group 2); 9 patients with disseminated tuberculosis (group 3); 49 patients with pulmonary tuberculosis (group 4); and 48 healthy controls (group 5). Clinical histories were recorded, and blood specimens were obtained. RESULTS: Patients in groups 1 and 2 had CD4+ T-lymphocyte counts that were similar to those in patients in groups 4 and 5, and they were not infected with the human immunodeficiency virus (HIV). Washed cells obtained from patients in groups 1 and 2 had intact cytokine production and a response to cytokine stimulation. In contrast, plasma obtained from these patients inhibited the activity of interferon-γ in normal cells. High-titer anti-interferon-γ autoantibodies were detected in 81% of patients in group 1, 96% of patients in group 2, 11% of patients in group 3, 2% of patients in group 4, and 2% of controls (group 5). Forty other anticytokine autoantibodies were assayed. One patient with cryptococcal meningitis had autoantibodies only against granulocyte-macrophage colony-stimulating factor. No other anticytokine autoantibodies or genetic defects correlated with infections. There was no familial clustering. CONCLUSIONS: Neutralizing anti-interferon-γ autoantibodies were detected in 88% of Asian adults with multiple opportunistic infections and were associated with an adult-onset immunodeficiency akin to that of advanced HIV infection. (Funded by the National Institute of Allergy and Infectious Diseases and the National Institute of Dental and Craniofacial Research; ClinicalTrials.gov number, NCT00814827.).


Assuntos
Anticorpos Neutralizantes/sangue , Autoanticorpos/sangue , Doenças Autoimunes/imunologia , Interferon gama/imunologia , Infecções por Mycobacterium/imunologia , Infecções Oportunistas/imunologia , Adolescente , Adulto , Idade de Início , Idoso , Contagem de Linfócito CD4 , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Micoses/imunologia , Taiwan , Tailândia , Tuberculose Pulmonar/imunologia , Adulto Jovem
3.
Blood ; 119(17): 3933-9, 2012 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-22403254

RESUMO

Patients with anti-IFN-γ autoantibodies have impaired IFN-γ signaling, leading to severe disseminated infections with intracellular pathogens, especially nontuberculous mycobacteria. Disease may be severe and progressive, despite aggressive treatment. To address the underlying pathogenic IFN-γ autoantibodies we used the therapeutic monoclonal rituximab (anti-CD20) to target patient B cells. All subjects received between 8 and 12 doses of rituximab within the first year to maintain disease remission. Subsequent doses were given for relapsed infection. We report 4 patients with refractory disease treated with rituximab who had clinical and laboratory evidence of therapeutic response as determined by clearance of infection, resolution of inflammation, reduction of anti-IFN-γ autoantibody levels, and improved IFN-γ signaling.


Assuntos
Anticorpos Monoclonais Murinos/uso terapêutico , Autoanticorpos/imunologia , Linfócitos B/imunologia , Fatores Imunológicos/uso terapêutico , Interferon gama/imunologia , Infecções por Mycobacterium não Tuberculosas/imunologia , Infecções por Mycobacterium/tratamento farmacológico , Idoso , Western Blotting , Feminino , Citometria de Fluxo , Humanos , Interferon gama/farmacologia , Pessoa de Meia-Idade , Infecções por Mycobacterium/imunologia , Infecções por Mycobacterium/microbiologia , Fosforilação , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Rituximab , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo
4.
Blood ; 116(23): 4848-58, 2010 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-20716769

RESUMO

Patients with thymic malignancy have high rates of autoimmunity leading to a variety of autoimmune diseases, most commonly myasthenia gravis caused by anti-acetylcholine receptor autoantibodies. High rates of autoantibodies to cytokines have also been described, although prevalence, spectrum, and functionality of these anti-cytokine autoantibodies are poorly defined. To better understand the presence and function of anti-cytokine autoantibodies, we created a luciferase immunoprecipitation system panel to search for autoantibodies against 39 different cytokines and examined plasma from controls (n = 30) and patients with thymic neoplasia (n = 17). In this screen, our patients showed statistically elevated, but highly heterogeneous immunoreactivity against 16 of the 39 cytokines. Some patients showed autoantibodies to multiple cytokines. Functional testing proved that autoantibodies directed against interferon-α, interferon-ß, interleukin-1α (IL-1α), IL-12p35, IL-12p40, and IL-17A had biologic blocking activity in vitro. All patients with opportunistic infection showed multiple anti-cytokine autoantibodies (range 3-11), suggesting that anti-cytokine autoantibodies may be important in the pathogenesis of opportunistic infections in patients with thymic malignancy. This study was registered at http://clinicaltrials.gov as NCT00001355.


Assuntos
Autoanticorpos/sangue , Citocinas/imunologia , Infecções Oportunistas/imunologia , Neoplasias do Timo/complicações , Neoplasias do Timo/imunologia , Adulto , Idoso , Autoantígenos/imunologia , Feminino , Humanos , Imunoensaio , Immunoblotting , Imunoprecipitação , Masculino , Pessoa de Meia-Idade , Infecções Oportunistas/sangue , Infecções Oportunistas/epidemiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias do Timo/sangue , Adulto Jovem
5.
J Phys Chem A ; 116(16): 4137-43, 2012 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-22462398

RESUMO

Photoelectric charging experiments measure heterogeneous uptake coefficients for pyrene on model marine aerosol particles, including NaCl, NaNO(3), and MgCl(2). The analysis employs a multilayer kinetic model that contains adsorption and desorption rate constants for the bare aerosol surface and for pyrene-coated surfaces. First coating the aerosol particles with a pyrene layer and following the desorption using both t-DMA and photoelectric charging yields the desorption rate constants. Separate experiments monitor the increase in surface coverage of initially bare aerosol particles after exposure to pyrene vapor in a sliding-injector flow tube. Analyzing these data using the multilayer model constrained by the measured desorption rate constants yields the adsorption rate constants. The calculated initial heterogeneous uptake coefficient, γ(0)(295 K), is 1.1 × 10(-3) for NaCl, 6.6 × 10(-4) for NaNO(3), and 6.0 × 10(-4) for MgCl(2). The results suggest that a free energy barrier controls the uptake rate rather than kinematics.

6.
PLoS One ; 17(3): e0265871, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35320317

RESUMO

BACKGROUND: Pneumonia is the leading cause of death in children globally with the majority of these deaths observed in resource-limited settings. Globally, the annual incidence of clinical pneumonia in under-five children is approximately 152 million, mostly in the low- and middle-income countries. Of these, 8.7% progressed to severe pneumonia requiring hospitalization. However, data to predict children at the greatest risk to develop severe pneumonia from pneumonia are limited. METHOD: Secondary data analysis was performed after extracting relevant data from a prospective cluster randomized controlled clinical trial; children of either sex, aged two months to five years with pneumonia or severe pneumonia acquired in the community were enrolled over a period of three years in 16 clusters in urban Dhaka city. RESULTS: The analysis comprised of 2,597 children aged 2-59 months. Of these, 904 and 1693 were categorized as pneumonia (controls) and severe pneumonia (cases), respectively based on WHO criteria. The median age of children was 9.2 months (inter quartile range, 5.1-17.1) and 1,576 (60%) were male. After adjustment for covariates, children with temperature ≥38°C, duration of illness ≥3 days, male sex, received prior medical care and severe stunting showed a significantly increased likelihood of developing severe pneumonia compared to those with pneumonia. Severe pneumonia in children occurred more often in older children who presented commonly from wealthy quintile families, and who often sought care from private facilities in urban settings. CONCLUSION AND RECOMMENDATION: Male sex, longer duration of illness, fever, received prior medical care, and severe stunting were significantly associated with development of WHO-defined severe childhood pneumonia in our population. The results of this study may help to develop interventions target to reduce childhood morbidity and mortality of children suffering from severe pneumonia.


Assuntos
Infecções Comunitárias Adquiridas , Pneumonia , Bangladesh/epidemiologia , Estudos de Casos e Controles , Criança , Infecções Comunitárias Adquiridas/complicações , Infecções Comunitárias Adquiridas/epidemiologia , Feminino , Transtornos do Crescimento/complicações , Humanos , Lactente , Masculino , Pneumonia/complicações , Estudos Prospectivos
7.
PLoS One ; 14(6): e0218248, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31216314

RESUMO

The advent of smartphones has advanced the use of embedded sensors to acquire various physiological information. For example, smartphone camera sensors and accelerometers can provide heart rhythm signals to the subjects, while microphones can give respiratory signals. However, the acquired smartphone-based physiological signals are more vulnerable to motion and noise artifacts (MNAs) compared to using medical devices, since subjects need to hold the smartphone with proper contact to the smartphone camera and lens stably and tightly for a duration of time without any movement in the hand or finger. This results in more MNA than traditional methods, such as placing a finger inside a tightly enclosed pulse oximeter to get PPG signals, which provides stable contact between the sensor and the subject's finger. Moreover, a smartphone lens does not block ambient light in an effective way, while pulse oximeters are designed to block the ambient light effectively. In this paper, we propose a novel diversity method for smartphone signals that reduces the effect of MNAs during heart rhythm signal detection by 1) acquiring two heterogeneous signals from a color intensity signal and a fingertip movement signal, and 2) selecting the less MNA-corrupted signal of the two signals. The proposed method has advantages in that 1) diversity gain can be obtained from the two heterogeneous signals when one signal is clean while the other signal is corrupted, and 2) acquisition of the two heterogeneous signals does not double the acquisition procedure but maintains a single acquisition procedure, since two heterogeneous signals can be obtained from a single smartphone camera recording. In our diversity method, we propose to choose the better signal based on the signal quality indices (SQIs), i.e., standard deviation of instantaneous heart rate (STD-HR), root mean square of the successive differences of peak-to-peak time intervals (RMSSD-T), and standard deviation of peak values (STD-PV). As a performance metric evaluating the proposed diversity method, the ratio of usable period is considered. Experimental results show that our diversity method increases the usable period 19.53% and 6.25% compared to the color intensity or the fingertip movement signals only, respectively.


Assuntos
Frequência Cardíaca/fisiologia , Coração/fisiologia , Monitorização Fisiológica , Smartphone , Algoritmos , Dedos/fisiologia , Humanos , Movimento (Física) , Oximetria/métodos , Processamento de Sinais Assistido por Computador , Máquina de Vetores de Suporte
8.
J Neurosurg Pediatr ; 21(5): 528-534, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29424629

RESUMO

OBJECTIVE Parental presence in the operating room during the induction of anesthesia (PPIA) has been shown to decrease parent and child anxiety and increase satisfaction with patient experience in outpatient otolaryngological procedures, such as tympanostomy tube placement. PPIA for other procedures, such as a major neurosurgical intervention, has been a practice at the authors' institutions for many years. This practice is not universally accepted across the United States, and the potential benefits for patients and families have not been formally evaluated. The aim of this study is to provide a qualitative analysis of parental and patient satisfaction with PPIA at the authors' institution. METHODS All patients younger than 18 years who underwent surgical intervention at the authors' institution between August 2013 and December 2015 were identified. All surgeries were performed by a single neurosurgeon. A random sample of 96 parents were contacted by telephone for a qualitative, semiscripted interview; 42 parents completed the interviews. The interview consisted of a validated satisfaction assessment in addition to a standardized open-ended questionnaire. Thematic analysis was performed until saturation was achieved, and responses were coded into the predominant themes. Member checking was performed, and a thick description was created. RESULTS The predominant themes identified with PPIA were 1) perception of induction as traumatizing or distressing to witness, 2) positive feelings regarding having been present, 3) satisfaction regarding the overall experience with surgery, 4) variable feelings in parents who decided not to attend induction, and 5) mixed feelings in the interactions with the care team. Parents expressed an array of positive, negative, and neutral impressions of the experience; however, overall, most experiences were positive. Most parents would choose PPIA again if their child required additional surgery. CONCLUSIONS This is the first study to evaluate the benefit of PPIA for pediatric neurosurgical patients. The results show a unique insight into medical communication and patient satisfaction with high-risk surgeries. PPIA may be able to help shape an environment of trust and increase satisfaction with perioperative care.


Assuntos
Anestesia/psicologia , Procedimentos Neurocirúrgicos/psicologia , Pais/psicologia , Satisfação Pessoal , Ansiedade/etiologia , Criança , Feminino , Humanos , Masculino , Salas Cirúrgicas , Relações Pais-Filho , Satisfação do Paciente , Estudos Retrospectivos , Inquéritos e Questionários
9.
World Neurosurg ; 114: e1007-e1015, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29597016

RESUMO

OBJECTIVE: Although the primary goal of treatment of type II odontoid fracture is bony union, some advocate continued nonsurgical management of minimally symptomatic older patients who have fibrous union or minimal fracture motion. The risk of this strategy is unknown. We reviewed our long-term outcomes after dens nonunion to define the natural history of Type II odontoid fractures in elderly patients managed nonoperatively. METHODS: A retrospective chart review of 50 consecutive adults aged 65 or older with Type II odontoid fracture initially managed nonsurgically from 1998 to 2012 at a single tertiary care institution was conducted. Particular attention was paid to patients who had orthosis removal despite absent bony fusion. Patients were contacted prospectively by telephone and followed until death, surgical intervention, or last known contact. RESULTS: Fifty patients initially were managed nonsurgically; of these, 21 (42.0%) proceeded to bony fusion, 3 (6%) underwent delayed surgery for persistent instability, and 26 (52%) had orthosis removal despite the lack of solid arthrodesis on imaging. The last group had a median follow-up of 25 months (range 4-158 months), with 20 of 26 (76.9%) followed until death. Of these patients, 1 patient developed progressive quadriplegia and dysphagia 11 months after initial injury. Compared with patients with spontaneous union, patients with nonunion had shorter life expectancy, despite no significant differences between the groups with respect to age, sex, injury mechanism, radiographic variables, or follow-up duration. CONCLUSIONS: Orthosis removal despite fracture nonunion may be reasonable in elderly patients with Type II dens fractures.


Assuntos
Gerenciamento Clínico , Processo Odontoide/diagnóstico por imagem , Processo Odontoide/lesões , Pseudoartrose/diagnóstico por imagem , Fraturas da Coluna Vertebral/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Seguimentos , Humanos , Masculino , Pseudoartrose/terapia , Estudos Retrospectivos , Fraturas da Coluna Vertebral/terapia , Resultado do Tratamento
10.
J Neurosurg ; 121(4): 944-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25061865

RESUMO

OBJECTIVES: Many neurosurgeons obtain repeat head CT at the first clinic follow-up visit for nonoperative cerebral contusion and traumatic subarachnoid hemorrhage (tSAH). The authors undertook a single-center, retrospective study to determine whether outpatient CT altered clinical decision-making. METHODS: The authors evaluated 173 consecutive adult patients admitted to their institution from April 2006 to August 2012 with an admission diagnosis of cerebral contusion or tSAH and at least 1 clinic follow-up visit with CT. Patients with epidural, subdural, aneurysmal subarachnoid, or intraventricular hemorrhage, and those who underwent craniotomy, were excluded. Patient charts were reviewed for new CT findings, new patient symptoms, and changes in treatment plan. Patients were stratified by neurological symptoms into 3 groups: 1) asymptomatic; 2) mild, nonspecific symptoms; and 3) significant symptoms. Mild, nonspecific symptoms included minor headaches, vertigo, fatigue, and mild difficulties with concentration, short-term memory, or sleep; significant symptoms included moderate to severe headaches, nausea, vomiting, focal neurological complaints, impaired consciousness, or new cognitive impairment evident on routine clinical examination. RESULTS: One hundred seventy-three patients met inclusion criteria, with initial clinic follow-up obtained within approximately 6 weeks. Of the 173 patients, 104 (60.1%) were asymptomatic, 68 patients (39.3%) had mild, nonspecific neurological symptoms, and 1 patient (1.0%) had significant neurological symptoms. Of the asymptomatic patients, 3 patients (2.9%) had new CT findings and 1 of these patients (1.0%) underwent a change in treatment plan because of these findings. This change involved an additional clinic appointment and CT to monitor a 12-mm chronic subdural hematoma that ultimately resolved without treatment. Of the patients with mild, nonspecific neurological symptoms, 6 patients (8.8%) had new CT findings and 3 of these patients (4.4%) underwent a change in treatment plan because of these findings; none of these patients required surgical intervention. The single patient with significant neurological symptoms did not have any new CT findings. CONCLUSIONS: Repeat outpatient CT of asymptomatic patients after nonoperative cerebral contusion and tSAH is very unlikely to demonstrate significant new pathology. Given the cost and radiation exposure associated with CT, imaging should be reserved for patients with significant symptoms or focal findings on neurological examination.


Assuntos
Lesões Encefálicas/diagnóstico por imagem , Lesões Encefálicas/terapia , Planejamento de Assistência ao Paciente , Hemorragia Subaracnoídea Traumática/diagnóstico por imagem , Hemorragia Subaracnoídea Traumática/terapia , Tomografia Computadorizada por Raios X , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neuroimagem , Pacientes Ambulatoriais , Estudos Retrospectivos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA