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1.
Ana E Bergues Pupo Juan Bory Reyes Luis E Bergues Cabrales Jesús M Bergues Cabrales 《Biomedical engineering online》2011,10(1):1-14
Background
During the cardiac cycle, the heart normally produces repeatable physiological sounds. However, under pathologic conditions, such as with heart valve stenosis or a ventricular septal defect, blood flow turbulence leads to the production of additional sounds, called murmurs. Murmurs are random in nature, while the underlying heart sounds are not (being deterministic).Innovation
We show that a new analytical technique, which we call Digital Subtraction Phonocardiography (DSP), can be used to separate the random murmur component of the phonocardiogram from the underlying deterministic heart sounds.Methods
We digitally recorded the phonocardiogram from the anterior chest wall in 60 infants and adults using a high-speed USB interface and the program Gold Wave http://www.goldwave.com. The recordings included individuals with cardiac structural disease as well as recordings from normal individuals and from individuals with innocent heart murmurs. Digital Subtraction Analysis of the signal was performed using a custom computer program called Murmurgram. In essence, this program subtracts the recorded sound from two adjacent cardiac cycles to produce a difference signal, herein called a "murmurgram". Other software used included Spectrogram (Version 16), GoldWave (Version 5.55) as well as custom MATLAB code.Results
Our preliminary data is presented as a series of eight cases. These cases show how advanced signal processing techniques can be used to separate heart sounds from murmurs. Note that these results are preliminary in that normal ranges for obtained test results have not yet been established.Conclusions
Cardiac murmurs can be separated from underlying deterministic heart sounds using DSP. DSP has the potential to become a reliable and economical new diagnostic approach to screening for structural heart disease. However, DSP must be further evaluated in a large series of patients with well-characterized pathology to determine its clinical potential. 相似文献2.
Oliver Tafel Philipp Latzin Karl Paul Tobias Winter Markus Woischnik Matthias Griese 《BMC pulmonary medicine》2008,8(1):1-8
Background
The reported diagnostic yield from bronchoscopies in patients with lung cancer varies greatly. The optimal combination of sampling techniques has not been finally established. The objectives of this study were to find the predictors of diagnostic yield in bronchoscopy and to evaluate different combinations of sampling techniques.Methods
All bronchoscopies performed on suspicion of lung malignancy in 2003 and 2004 were reviewed, and 363 patients with proven malignant lung disease were included in the study. Sampling techniques performed were biopsy, transbronchial needle aspiration (TBNA), brushing, small volume lavage (SVL), and aspiration of fluid from the entire procedure. Logistic regression analyses were adjusted for sex, age, endobronchial visibility, localization (lobe), distance from carina, and tumor size.Results
The adjusted odds ratios (OR) with 95% confidence intervals (CI) for a positive diagnostic yield through all procedures were 17.0 (8.5–34.0) for endobronchial lesions, and 2.6 (1.3–5.2) for constriction/compression, compared to non-visible lesions; 3.8 (1.3–10.7) for lesions > 4 cm, 6.7 (2.1–21.8) for lesions 3–4 cm, and 2.5 (0.8–7.9) for lesions 2–3 cm compared with lesions <= 2 cm. The combined diagnostic yield of biopsy and TBNA was 83.7% for endobronchial lesions and 54.2% for the combined group without visible lesions. This was superior to either technique alone, whereas additional brushing, SVL, and aspiration did not significantly increase the diagnostic yield.Conclusion
In patients with malignant lung disease, visible lesions and larger tumor size were significant predictors of higher diagnostic yield, after adjustment for sex, age, distance from carina, side and lobe. The combined diagnostic yield of biopsy and TBNA was significant higher than with either technique alone. 相似文献3.
Maurizia Capuzzo Marco Rambaldi Giovanni Pinelli Manuela Campesato Antonia Pigna Marco Zanello Maria Barbagallo Massimo Girardis Elena Toschi 《BMC anesthesiology》2012,12(1):1-8
Background
The Functional Comorbidity Index (FCI) was recently developed to predict physical function in acute lung injury patients using comorbidity data. Our objectives were to determine: (1) the inter-rater reliability of the FCI collected using in-patient discharge summaries (primary objective); and (2) the accuracy and predictive validity of the FCI collected using hospital discharge summaries and admission records versus complete chart review (secondary objectives).Methods
For reliability, we evaluated the FCI’s intraclass correlation coefficient (ICC) among trained research staff performing data collection for 421 acute lung injury patients enrolled in a prospective cohort study. For validity and accuracy, we compared the detection of FCI comorbidities across three types of inpatient medical records, and the association of the respective FCI scores obtained with patients’ SF-36 physical function subscale (PFS) scores at 1-year follow-up.Results
Inter-rater reliability was near-perfect (ICC 0.91; 95% CI 0.89-0.94). Hospital admission records and discharge summaries (vs. complete chart review) significantly underestimated the total FCI score. However, using multivariable linear regression, FCI scores collected using each of the three types of inpatient medical records had similar associations with PFS, suggesting similar predictive value.Conclusions
Data collection using in-patient discharge summaries represents a reliable and valid method for collecting FCI comorbidity information. 相似文献4.
Kim H Blomqvist Jesper Lundbom Nina Lundbom Raimo E Sepponen 《Biomedical engineering online》2011,10(1):1-9
Background
Parkinson's disease (PD) is a neurodegenerative disorder resulting in motor disturbances that can impact normal gait. Although PD initially responds well to pharmacological treatment, as the disease progresses efficacy often fluctuates over the course of the day, and clinical management would benefit from long-term objective measures of gait. We have previously described a small device worn on the shank that uses acceleration and angular velocity sensors to calculate stride length and identify freezing of gait in PD patients. In this study we extend validation of the gait monitor to 24-h using simultaneous video observation of PD patients.Methods
A sleep laboratory was adapted to perform 24-hr video monitoring of patients while wearing the device. Continuous video monitoring of a sleep lab, hallway, kitchen and conference room was performed using a 4-camera security system and recorded to hard disk. Subjects (3) wore the gait monitor on the left shank (just above the ankle) for a 24-h period beginning around 5 pm in the evening. Accuracy of stride length measures were assessed at the beginning and end of the 24-h epoch. Two independent observers rated the video logs to identify when subjects were walking or lying down.Results
The mean error in stride length at the start of recording was 0.05 m (SD 0) and at the conclusion of the 24 h epoch was 0.06 m (SD 0.026). There was full agreement between observer coding of the video logs and the output from the gait monitor software; that is, for every video observation of the subject walking there was a corresponding pulse in the monitor data that indicated gait.Conclusions
The accuracy of ambulatory stride length measurement was maintained over the 24-h period, and there was 100% agreement between the autonomous detection of locomotion by the gait monitor and video observation. 相似文献5.
Quignon P Giraud M Rimbault M Lavigne P Tacher S Morin E Retout E Valin AS Lindblad-Toh K Nicolas J Galibert F 《Genome biology》2005,6(10):R83-9
Background
Dogs and rats have a highly developed capability to detect and identify odorant molecules, even at minute concentrations. Previous analyses have shown that the olfactory receptors (ORs) that specifically bind odorant molecules are encoded by the largest gene family sequenced in mammals so far.Results
We identified five amino acid patterns characteristic of ORs in the recently sequenced boxer dog and brown Norway rat genomes. Using these patterns, we retrieved 1,094 dog genes and 1,493 rat genes from these shotgun sequences. The retrieved sequences constitute the olfactory receptor repertoires of these two animals. Subsets of 20.3% (for the dog) and 19.5% (for the rat) of these genes were annotated as pseudogenes as they had one or several mutations interrupting their open reading frames. We performed phylogenetic studies and organized these two repertoires into classes, families and subfamilies.Conclusion
We have established a complete or almost complete list of OR genes in the dog and the rat and have compared the sequences of these genes within and between the two species. Our results provide insight into the evolutionary development of these genes and the local amplifications that have led to the specific amplification of many subfamilies. We have also compared the human and rat ORs with the human and mouse OR repertoires. 相似文献6.
7.
Ian B Masters Robert S Ware Paul V Zimmerman Brian Lovell Richard Wootton Paul V Francis Anne B Chang 《BMC pulmonary medicine》2006,6(1):1-8
Background
Detecting serum antibody against inhaled antigens is an important diagnostic adjunct for hypersensitivity pneumonitis (HP). We sought to validate a quantitative fluorimetric assay testing serum from bird fanciers.Methods
Antibody activity was assessed in bird fanciers and control subjects using various avian antigens and serological methods, and the titer was compared with symptoms of HP.Results
IgG antibody against pigeon serum antigens, quantified by fluorimetry, provided a good discriminator of disease. Levels below 10 mg/L were insignificant, and increasing titers were associated with disease. The assay was unaffected by total IgG, autoantibodies and antibody to dietary hen's egg antigens. Antigens from pigeon serum seem sufficient to recognize immune sensitivity to most common pet avian species. Decreasing antibody titers confirmed antigen avoidance.Conclusion
Increasing antibody titer reflected the likelihood of HP, and decreasing titers confirmed antigen avoidance. Quantifying antibody was rapid and the increased sensitivity will improve the rate of false-negative reporting and obviate the need for invasive diagnostic procedures. Automated fluorimetry provides a method for the international standardization of HP serology thereby improving quality control and improving its suitability as a diagnostic adjunct. 相似文献8.
9.
Tomáš Helikar Bryan Kowal Sean McClenathan Mitchell Bruckner Thaine Rowley Alex Madrahimov Ben Wicks Manish Shrestha Kahani Limbu Jim A Rogers 《BMC systems biology》2012,6(1):1-14
Background
The construction of customized nucleic acid sequences allows us to have greater flexibility in gene design for recombinant protein expression. Among the various parameters considered for such DNA sequence design, individual codon usage (ICU) has been implicated as one of the most crucial factors affecting mRNA translational efficiency. However, previous works have also reported the significant influence of codon pair usage, also known as codon context (CC), on the level of protein expression.Results
In this study, we have developed novel computational procedures for evaluating the relative importance of optimizing ICU and CC for enhancing protein expression. By formulating appropriate mathematical expressions to quantify the ICU and CC fitness of a coding sequence, optimization procedures based on genetic algorithm were employed to maximize its ICU and/or CC fitness. Surprisingly, the in silico validation of the resultant optimized DNA sequences for Escherichia coli, Lactococcus lactis, Pichia pastoris and Saccharomyces cerevisiae suggests that CC is a more relevant design criterion than the commonly considered ICU.Conclusions
The proposed CC optimization framework can complement and enhance the capabilities of current gene design tools, with potential applications to heterologous protein production and even vaccine development in synthetic biotechnology. 相似文献10.
11.
H.-C. Lai W.-L. Lee K.-Y. Wang C.-T. Ting C.-S. Su T.-J. Liu 《Netherlands heart journal》2011,19(9):379-385
Background
Late-onset proximal coronary artery stenosis caused by preceding percutaneous catheterisation procedures remains under-surveyed.Methods
From 1993, all patients undergoing percutaneous coronary procedures and a second session within 3 years were included except those ever treated by coronary bypass surgery or chest radiotherapy during this 3-year period. Emergence of a new lesion or worsening of an initially insignificant lesion to >50% of diameter stenosis at the never-treated ostial/proximal coronary segment on the follow-up angiogram was defined as late coronary stenosis caused by the previous catheterisation procedure and was analysed.Results
From January 1993 to December 2005, 3240 patients who underwent 5025 procedures met the inclusion criteria. Of them, 23 patients experienced an event of late coronary artery stenosis (overall incidence 0.46%), and interventional procedures, specifically shaped catheters (Voda, XB, Amplatz Left) and atherosclerosis vulnerability correlated with risks of adverse events. Most of these events could be managed by contemporary medical, interventional, or surgical strategies, yet hazards of mortality and long-term restenosis still existed from this catheter-induced complication.Conclusions
Percutaneous catheterisation procedures could be complicated by late proximal coronary artery stenosis. Thus, when conducting these procedures, operators should select and manipulate catheters with caution, especially in patients with susceptible clinical characteristics. 相似文献12.
Background
Most molecular biology experiments, and the techniques associated with this field of study, involve a great deal of engineering in the form of molecular cloning. Like all forms of engineering, perfect information about the starting material is crucial for successful completion of design and strategies.Results
We have generated a program that allows complete in silico simulation of the cloning experiment. Starting with a primary DNA sequence, PlasmaDNA looks for restriction sites, open reading frames, primer annealing sequences, and various common domains. The databases are easily expandable by the user to fit his most common cloning needs. PlasmaDNA can manage and graphically represent multiple sequences at the same time, and keeps in memory the overhangs at the end of the sequences if any. This means that it is possible to virtually digest fragments, to add the digestion products to the project, and to ligate together fragments with compatible ends to generate the new sequences. Polymerase Chain Reaction (PCR) fragments can also be virtually generated using the primer database, automatically adding to the fragments any 5' extra sequences present in the primers.Conclusion
PlasmaDNA is a program available both on Windows and Apple operating systems, designed to facilitate molecular cloning experiments by building a visual map of the DNA. It then allows the complete planning and simulation of the cloning experiment. It also automatically updates the new sequences generated in the process, which is an important help in practice. The capacity to maintain multiple sequences in the same file can also be used to archive the various steps and strategies involved in the cloning of each construct. The program is freely available for download without charge or restriction. 相似文献13.
Gholami GA Aghaloo M Ghanavati F Amid R Kadkhodazadeh M 《Annals of surgical innovation and research》2012,6(1):3-6
Background
A cursory review of the current socket preservation literatures well depicts the necessity of further esthetic considerations through the corrective procedures of the alveolar ridge upon and post extraction. A new technique has been described here is a rotational pedicle combined epithelialized and connective tissue graft (RPC graft) adjunct with immediate guided tissue regeneration (GBR) procedure.Results
We reviewed this technique through a case report and discuss it??s benefit in compare to other socket preservation procedures.Conclusion
The main advantages of RPC graft would be summarized as follows: stable primary closure during bone remodeling, saving or crating sufficient vestibular depth, making adequate keratinized gingiva on the buccal surface, and being esthetically pleasant. 相似文献14.
15.
Cava Claudia Zoppis Italo Gariboldi Manuela Castiglioni Isabella Mauri Giancarlo Antoniotti Marco 《Journal of clinical bioinformatics》2014,4(1):1-13
Background
The human body plays host to a vast array of bacteria, found in oral cavities, skin, gastrointestinal tract and the vagina. Some bacteria are harmful while others are beneficial to the host. Despite the availability of many methods to identify bacteria, most of them are only applicable to specific and cultivable bacteria and are also tedious. Based on high throughput sequencing technology, this work derives 16S rRNA sequences of bacteria and analyzes probiotics and pathogens species.Results
We constructed a database that recorded the species of probiotics and pathogens from literature, along with a modified Smith-Waterman algorithm for assigning the taxonomy of the sequenced 16S rRNA sequences. We also constructed a bacteria disease risk model for seven diseases based on 98 samples. Applicability of the proposed platform is demonstrated by collecting the microbiome in human gut of 13 samples.Conclusions
The proposed platform provides a relatively easy means of identifying a certain amount of bacteria and their species (including uncultivable pathogens) for clinical microbiology applications. That is, detecting how probiotics and pathogens inhabit humans and how affect their health can significantly contribute to develop a diagnosis and treatment method. 相似文献16.
Background
Ultrasound-guided diagnostic breast biopsy technology represents the current standard of care for the evaluation of indeterminate and suspicious lesions seen on diagnostic breast ultrasound. Yet, there remains much debate as to which particular method of ultrasound-guided diagnostic breast biopsy provides the most accurate and optimal diagnostic information. The aim of the current study was to compare and contrast the 8-gauge vacuum-assisted biopsy approach and the spring-loaded 14-gauge core biopsy approach.Methods
A retrospective analysis was done of all ultrasound-guided diagnostic breast biopsy procedures performed by either the 8-gauge vacuum-assisted biopsy approach or the spring-loaded 14-gauge core biopsy approach by a single surgeon from July 2001 through June 2009.Results
Among 1443 ultrasound-guided diagnostic breast biopsy procedures performed, 724 (50.2%) were by the 8-gauge vacuum-assisted biopsy technique and 719 (49.8%) were by the spring-loaded 14-gauge core biopsy technique. The total number of false negative cases (i.e., benign findings instead of invasive breast carcinoma) was significantly greater (P = 0.008) in the spring-loaded 14-gauge core biopsy group (8/681, 1.2%) as compared to in the 8-gauge vacuum-assisted biopsy group (0/652, 0%), with an overall false negative rate of 2.1% (8/386) for the spring-loaded 14-gauge core biopsy group as compared to 0% (0/148) for the 8-gauge vacuum-assisted biopsy group. Significantly more (P < 0.001) patients in the spring-loaded 14-gauge core biopsy group (81/719, 11.3%) than in the 8-gauge vacuum-assisted biopsy group (18/724, 2.5%) were recommended for further diagnostic surgical removal of additional tissue from the same anatomical site of the affected breast in an immediate fashion for indeterminate/inconclusive findings seen on the original ultrasound-guided diagnostic breast biopsy procedure. Significantly more (P < 0.001) patients in the spring-loaded 14-gauge core biopsy group (54/719, 7.5%) than in the 8-gauge vacuum-assisted biopsy group (9/724, 1.2%) personally requested further diagnostic surgical removal of additional tissue from the same anatomical site of the affected breast in an immediate fashion for a benign finding seen on the original ultrasound-guided diagnostic breast biopsy procedure.Conclusions
In appropriately selected cases, the 8-gauge vacuum-assisted biopsy approach appears to be advantageous to the spring-loaded 14-gauge core biopsy approach for providing the most accurate and optimal diagnostic information. 相似文献17.
Diego Garcia-Borreguero Paul Stillman Heike Benes Heiner Buschmann K Ray Chaudhuri Victor M Gonzalez Rodríguez Birgit Högl Ralf Kohnen Giorgio Carlo Monti Karin Stiasny-Kolster Claudia Trenkwalder Anne-Marie Williams Marco Zucconi 《BMC neurology》2011,11(1):1-13
Background
Restless legs syndrome (RLS) is a neurological disorder with a lifetime prevalence of 3-10%. in European studies. However, the diagnosis of RLS in primary care remains low and mistreatment is common.Methods
The current article reports on the considerations of RLS diagnosis and management that were made during a European Restless Legs Syndrome Study Group (EURLSSG)-sponsored task force consisting of experts and primary care practioners. The task force sought to develop a better understanding of barriers to diagnosis in primary care practice and overcome these barriers with diagnostic and treatment algorithms.Results
The barriers to diagnosis identified by the task force include the presentation of symptoms, the language used to describe them, the actual term "restless legs syndrome" and difficulties in the differential diagnosis of RLS.Conclusion
The EURLSSG task force reached a consensus and agreed on the diagnostic and treatment algorithms published here. 相似文献18.