Fetal Electrocardiogram Extraction and Analysis Using Adaptive Noise Cancellation and Wavelet Transformation Techniques

Birth defect-related demise is mainly due to congenital heart defects. In the earlier stage of pregnancy, fetus problem can be identified by finding information about the fetus to avoid stillbirths. The gold standard used to monitor the health status of the fetus is by Cardiotachography(CTG), cannot be used for long durations and continuous monitoring. There is a need for continuous and long duration monitoring of fetal ECG signals to study the progressive health status of the fetus using portable devices. The non-invasive method of electrocardiogram recording is one of the best method used to diagnose fetal cardiac problem rather than the invasive methods.The monitoring of the fECG requires development of a miniaturized hardware and a efficient signal processing algorithms to extract the fECG embedded in the mother ECG. The paper discusses a prototype hardware developed to monitor and record the raw mother ECG signal containing the fECG and a signal processing algorithm to extract the fetal Electro Cardiogram signal. We have proposed two methods of signal processing, first is based on the Least Mean Square (LMS) Adaptive Noise Cancellation technique and the other method is based on the Wavelet Transformation technique. A prototype hardware was designed and developed to acquire the raw ECG signal containing the mother and fetal ECG and the signal processing techniques were used to eliminate the noises and extract the fetal ECG and the fetal Heart Rate Variability was studied. Both the methods were evaluated with the signal acquired from a fetal ECG simulator, from the Physionet database and that acquired from the subject. Both the methods are evaluated by finding heart rate and its variability, amplitude spectrum and mean value of extracted fetal ECG. Also the accuracy, sensitivity and positive predictive value are also determined for fetal QRS detection technique. In this paper adaptive filtering technique uses Sign-sign LMS algorithm and wavelet techniques with Daubechies wavelet, employed along with de noising techniques for the extraction of fetal Electrocardiogram.Both the methods are having good sensitivity and accuracy. In adaptive method the sensitivity is 96.83, accuracy 89.87, wavelet sensitivity is 95.97 and accuracy is 88.5. Additionally, time domain parameters from the plot of heart rate variability of mother and fetus are analyzed.     

Lack of evidence for protease evolution in HIV-1-infected patients after 2 years of successful highly active antiretroviral therapy

The mechanisms involved in maintaining a latent replication-competent integrated human immunodeficiency virus type 1 (HIV-1) reservoir after successful highly active antiretroviral therapy (HAART) have not been fully described. The objective of this study was to assess whether low-level, persistent HIV-1 replication can be detected in the protease gene, in 10 HIV-1-infected patients who have undergone 2 years of successful HAART. Peripheral blood mononuclear cells (PBMCs) were collected from 10 HIV-1-infected patients receiving a triple-drug combination therapy (2 nucleoside analogues and 1 protease inhibitor). HIV-1 RNA levels and CD4+ and CD8+ T cell counts were longitudinally determined during a follow-up period of 108 weeks. Similarly, proviral fragments of the protease-coding region, obtained at baseline and at week 108 of HAART, were amplified by polymerase chain reaction from PBMCs, and 10-25 individual clones were sequenced for each time point. Only 1 of 271 individual protease clones showed a major resistance substitution (M46I [patient D]). Phylogenetic analysis revealed that, in all patients, the genetic distances from the deduced most recent common ancestor, in samples obtained at week 108 of HAART, were not longer than those in samples obtained at baseline. Moreover, the pattern of amino acid divergence during therapy showed an absence of positive selection in the protease-coding region. Taken together, these results show a lack of clinically relevant evolution in the protease-coding region after 2 years of successful HAART.     

Acute severe asthma

Acute exacerbations of asthma are very common reasons for a presentation to emergency departments. This paper focuses on defining the high‐risk group, consideration of the concept of phenotypes of acute asthma, the assessment of severe and life‐threatening exacerbations and an emphasis on the management of the more severe end of the exacerbation severity. A number of evidence‐based guidelines exist throughout the world and are all slightly different. This reflects the poor evidence base for some of those recommendations. Thus, a large variation of treatment drugs, doses and regimen are used and clearly not standardised. This paper aims to present a summary of the best evidence and discuss some of these controversies. The most important aspect of treating an exacerbation of acute asthma is to review regularly and assess response to treatment. Severe and life‐threatening episodes should be treated with early use of intravenous treatment in a stepwise manner following the local guidelines. Non‐invasive ventilation and high flow nasal cannulae delivery of oxygen in the emergency department are evolving modalities, but evidence for their use is currently limited.     

Nadir CA-125 concentration in the normal range as an independent prognostic factor for optimally treated advanced epithelial ovarian cancer.

BACKGROUND: The amount of residual disease after surgery is considered the most important factor influencing the survival of patients with advanced epithelial ovarian cancer (adEOC). In optimally treated patients with adEOC, there are no well-established prognostic factors [excluding International Federation of Gynecology and Obstetrics (FIGO) stage]. The aim of this retrospective study is to analyze the prognostic value of the CA-125 nadir after the completion of an optimal primary treatment. PATIENTS AND METHODS: Patients treated for adEOC were identified from January 1998 to December 2006. Inclusion criteria: elevated CA-125 at time of diagnosis (>35 kU/l); FIGO stage III-IV treated with optimal primary treatment (residual tumor <1 cm and carboplatin/taxane-based combination chemotherapy); and complete response to optimal primary treatment with normalization of CA-125. RESULTS: Patients, n = 96: 44 group A (< or =10 kU/l); 52 group B (11-35 kU/l). Median progression-free survival (PFS) was 42 and 20 months for groups A and B, respectively (P = 0.0087). Median overall survival (OS) was 84 and 43 months for groups A and B, respectively (P < 0.0001). The Cox model showed a highly significant impact on PFS and OS in relation to CA-125 nadir levels. CONCLUSIONS: The CA-125 nadir value is a strong independent prognostic factor for optimally treated adEOC after achieving a complete response.