Animal experimental models of ischemic limbs - A systematic review.

BACKGROUND: The objective of this systematic review is to summarize the available animal models of ischemic limbs, and to provide an overview of the advantages and disadvantages of each animal model and individual method of limb ischemia creation. METHODS: A review of literature was conducted using the PubMed and Web of Science pages. Various types of experimental animals and surgical approaches used in creating ischemic limbs were evaluated. Other outcomes of interest were the specific characteristics of the individual experimental animals, and duration of tissue ischemia. RESULTS: The most commonly used experimental animals were mice, followed by rabbits, rats, pigs, miniature pigs, and sheep. Single or double arterial ligation and excision of the entire femoral artery was the most often used method of ischemic limb creation. Other methods comprised single or double arterial electrocoagulation, use of ameroid constrictors, photochemically induced thrombosis, and different types of endovascular methods. The shortest duration of tissue ischemia was 7 days, the longest 90 days. CONCLUSIONS: This review shows that mice are among the most commonly used animals in limb ischemia research. Simple ligation and excision of the femoral artery is the most common method of creating an ischemic limb; nevertheless, it can result in acute rather than chronic ischemia. A two-stage sequential approach and methods using ameroid constrictors or endovascular blinded stent grafts are more suitable for creating a gradual arterial occlusion typically seen in humans. Selecting the right mouse strain or animal with artificially produced diabetes or hyperlipidaemia is crucial in chronic ischemic limb research. Moreover, the observation period following the onset of ischemia should last at least 14 days, preferably 4 weeks.

Comparison of the impact of autologous cell therapy and conservative standard treatment on tissue oxygen supply and course of the diabetic foot in patients with chronic limb-threatening ischemia: A randomized controlled trial.

Background: Autologous cell therapy (ACT) is a new treatment method for patients with diabetes and no-option chronic limb-threatening ischemia (NO-CLTI). We aimed to assess the impact of ACT on NO-CLTI in comparison with standard treatment (ST) in a randomized controlled trial. Methods: Diabetic patients with NO-CLTI were randomized to receive either ACT (n=21) or ST (n=19). After 12 weeks, those in the ST group, who did not improve were treated with ACT. The effect of ACT on ischemia and wound healing was assessed by changes in transcutaneous oxygen pressure (TcPO2) and the number of healed patients at 12 weeks. Pain was evaluated by Visual Analogue Scale (VAS). Amputation rates and amputation-free survival (AFS) were assessed in both groups. Results: During the first 12 weeks, TcPO2 increased in the ACT group from 20.8 ± 9.6 to 41.9 ± 18.3 mm Hg (p=0.005) whereas there was no change in the ST group (from 21.2 ± 11.4 to 23.9 ± 13.5 mm Hg). Difference in TcPO2 in the ACT group compared to ST group was 21.1 mm Hg (p=0.034) after 12 weeks. In the period from week 12 to week 24, when ST group received ACT, the TcPO2 in this group increased from 20.1 ± 13.9 to 41.9 ± 14.8 (p=0.005) while it did not change significantly in the ACT in this period. At 24 weeks, there was no significant difference in mean TcPO2 between the two groups. Wound healing was greater at 12 weeks in the ACT group compared to the ST group (5/16 vs. 0/13, p=0.048). Pain measured using VAS was reduced in the ACT group after 12 weeks compared to the baseline, and the difference in scores was again significant (p<0.001), but not in the ST group. There was no difference in rates of major amputation and AFS between ACT and ST groups at 12 weeks. Conclusions: This study has showed that ACT treatment in patients with no-option CLTI and diabetic foot significantly improved limb ischemia and wound healing after 12 weeks compared to conservative standard therapy. Larger randomized controlled trials are needed to study the benefits of ACT in patients with NO-CLTI and diabetic foot disease. Trial registration: The trial was registered in the National Board of Health (EudraCT 2016-001397-15).

A new database with annotations of P waves in ECGs with various types of arrhythmias.

Objective.The aim of this study is to create a database for the development, evaluation and objective comparison of algorithms for P wave detection in ECG signals.BrnoUniversity ofTechnology ECG SignalDatabase with Annotations ofP-Wave (BUT PDB) is an ECG signal database with marked peaks of P waves annotated by ECG experts. Currently, there are only a few databases of pathological ECG signals with P-wave annotations, and some are incorrect.Approach.The pathological ECG signals used in this work were selected from three existing databases of ECG signals: MIT-BIH Arrhythmia Database, MIT-BIH Supraventricular Arrhythmia Database and Long Term AF Database. The P-wave positions were manually annotated by two ECG experts in all selected signals.Main results.The final BUT PDB composed of selected signals consists of 50 two-minute, two-lead pathological ECG signal records with annotated P waves. Each record also contains a description of the diagnosis (pathology) present in the selected part of the record and information about positions and types of QRS complexes.Significance.The BUT PDB is created for developing new, more accurate and robust methods for P wave detection. These algorithms will be used in medical practice and will help cardiologists to evaluate ECG records, establish diagnoses and save time.

Comparison of Three Methods for Preparation of Autologous Cells for Use in Cell Therapy of Chronic Limb-Threatening Ischemia in People with Diabetes.

Autologous cell therapy (ACT) is a new therapeutic approach for diabetic patients with no-option chronic limb-threatening ischemia (NO-CLTI). The aim of our study was to quantify cell populations of cell therapy products (CTPs) obtained by three different isolation methods and to correlate their numbers with changes in transcutaneous oxygen pressure (TcPO2). CTPs were separated either from stimulated peripheral blood (PB) (n = 11) or harvested from bone marrow (BM) processed either by Harvest SmartPReP2 (n = 50) or sedimented with succinate gelatin (n = 29). The clinical effect was evaluated by the change in TcPO2 after 1, 3 and 6 months. TcPO2 increased significantly in all three methods at each time point in comparison with baseline values (p < .01) with no significant difference among them. There was no correlation between the change in TcPO2 and the size of injected cell populations. We only observed a weak correlation between the number of injected white blood cells (WBC) and an increase in TcPO2 at 1 and 3 months. Our study showed that all three isolation methods of ACT were similarly relatively efficient in the treatment of NO-CLTI. We observed no correlation of TcPO2 increase with the number of injected monocytes, lymphocytes or CD34+. We observed a weak correlation between TcPO2 increase and the number of injected WBCs.

Reliable P wave detection in pathological ECG signals.

Accurate automated detection of P waves in ECG allows to provide fast correct diagnosis of various cardiac arrhythmias and select suitable strategy for patients' treatment. However, P waves detection is a still challenging task, especially in long-term ECGs with manifested cardiac pathologies. Software tools used in medical practice usually fail to detect P waves under pathological conditions. Most of recently published approaches have not been tested on such the signals at all. Here we introduce a novel method for accurate and reliable P wave detection, which is success in both normal and pathological cases. Our method uses phasor transform of ECG and innovative decision rules in order to improve P waves detection in pathological signals. The rules are based on a deep knowledge of heart manifestation during various arrhythmias, such as atrial fibrillation, premature ventricular contraction, etc. By involving the rules into the decision process, we are able to find the P wave in the correct location or, alternatively, not to search for it at all. In contrast to another studies, we use three, highly variable annotated ECG databases, which contain both normal and pathological records, to objectively validate our algorithm. The results for physiological records are Se = 98.56% and PP = 99.82% for MIT-BIH Arrhythmia Database (MITDP, with MITDB P-Wave Annotations) and Se = 99.23% and PP = 99.12% for QT database. These results are comparable with other published methods. For pathological signals, the proposed method reaches Se = 96.40% and PP = 91.56% for MITDB and Se = 93.07% and PP = 88.60% for Brno University of Technology ECG Signal Database with Annotations of P wave (BUT PDB). In these signals, the proposed detector greatly outperforms other methods and, thus, represents a huge step towards effective use of fully automated ECG analysis in a real medical practice.

Animal experimental models of ischemic wounds - A review of literature.

Critical limb ischemia is a serious form of peripheral arterial disease (PAD). The consequences of lower limb ischemia are pain, claudication and chronic non-healing wounds. Patients with diabetes are especially at a high risk for developing non-healing ulcers. The most serious complication is major amputation. For this reason, there is a significant medical requirement to develop new therapies in order to prevent the progression of PAD. For research purposes, it is crucial to find an appropriate model of chronic ischemia to explore the processes of wound healing. According to recently acquired information, rodents are currently the most commonly used animals in these types of studies. The main advantage of using small animals is the low financial cost due to the relatively small demand for food, water and living space. The disadvantage is their anatomy, which is different from that of humans. Larger animals have a more human-like anatomy and physiology, but they require more expense and space for housing. A bipedicle skin flap and its modifications are popular models for ischemic wounds. In order to secure healing through re-epithelisation, as opposed to contraction in rodents, there is a need to remove the panniculus carnosus muscle. Wounds in other experimental animals heal primarily through re-epithelisation. The application of a silicone mesh underneath the flap prevents vascular regrowth in ischemic tissue. There is an ongoing effort to create in vivo diabetic models for chronic ulcer research. This work presents an overview of existing animal models of ischemic wounds.

Use of Waste Substrates for the Lipid Production by Yeasts of the Genus Metschnikowia-Screening Study.

Oleogenic yeasts are characterized by the ability to accumulate increased amounts of lipids under certain conditions. These microbial lipids differ in their fatty acid composition, which allows them to be widely used in the biotechnology industry. The interest of biotechnologists is closely linked to the rising prices of fossil fuels in recent years. Their negative environmental impact is caused by significantly increased demand for biodiesel. The composition of microbial lipids is very similar to vegetable oils, which provides great potential for use in the production of biodiesel. In addition, some oleogenic microorganisms are capable of producing lipids with a high proportion of unsaturated fatty acids. The presented paper's main aim was to study the production of lipids and lipid substances by yeasts of the genus Metschnikowia, to cultivate crude waste animal fat to study its utilization by yeasts, and to apply the idea of circular economy in the biotechnology of Metschnikowia yeasts. The work focuses on the influence of various stress factors in the cultivation process, such as reduced temperature or nutritional stress through the use of various waste substrates, together with manipulating the ratio of carbon and nitrogen sources in the medium. Yeast production properties were monitored by several instrumental techniques, including gas chromatography and Raman spectroscopy. The amount of lipids and in particular the fatty acid composition varied depending on the strains studied and the culture conditions used. The ability of yeast to produce significant amounts of unsaturated fatty acids was also demonstrated in the work. The most suitable substrate for lipid production was a medium containing glycerol, where the amount of accumulated lipids in the yeast M. pulcherrima 1232 was up to 36%. In our work, the crude animal fat was used for the production of high-value lipids, which to the best of our knowledge is a new result. Moreover, quantitative screening of lipase enzyme activity cultivated on animal fat substrate on selected yeasts of the genus Metschnikowia was performed. We found that for the yeast utilizing glycerol, animal fat seems to be an excellent source of carbon. Therefore, the yeast conversion of crude processed animal fat to value-added products is a valuable process for the biotechnology and food industry.

Production of Enriched Sporidiobolus sp. Yeast Biomass Cultivated on Mixed Coffee Hydrolyzate and Fat/Oil Waste Materials.

One of the most addressed topics today is the transfer from a linear model of economics to a model of circular economics. It is a discipline that seeks to eliminate waste produced by various industries. The food industry generates huge amounts of waste worldwide, particularly the coffee industry, and related industries produce millions of tons of waste a year. These wastes have potential utility in biotechnology, and in the production of energy, fuels, fertilizers and nutrients, using green techniques such as anaerobic digestion, co-digestion, composting, enzymatic action, and ultrasonic and hydrothermal carbonization. This work is focused on the biotechnological use of processed spent coffee grounds (SCG) and waste fat/oil materials by some Sporidiobolus sp. carotenogenic yeasts in the model of circular economics. The results show that selected yeast strains are able to grow on SCG hydrolysate and are resistant to antimicrobial compounds present in media. The most productive strain Sporidiobolus pararoseus CCY19-9-6 was chosen for bioreactor cultivation in media with a mixture of coffee lignocellulose fraction and some fat wastes. Sporidiobolus pararoseus CCY19-9-6 was able to produce more than 22 g/L of biomass in mixture of SCG hydrolysate and both coffee oil and frying oil. The combined waste substrates induced the production of lipidic metabolites, whereby the production of carotenoids exceeded 5 mg/g of dry biomass. On media with coffee oil, this strain produced high amounts of ubiquinone (8.265 ± 1.648 mg/g) and ergosterol (13.485 ± 1.275 mg/g). Overall, the results prove that a combination of waste substrates is a promising option for the production of carotenoid- and lipid-enriched yeast biomass.

Brno University of Technology Smartphone PPG Database (BUT PPG): Annotated Dataset for PPG Quality Assessment and Heart Rate Estimation.

To the best of our knowledge, there is no annotated database of PPG signals recorded by smartphone publicly available. This article introduces Brno University of Technology Smartphone PPG Database (BUT PPG) which is an original database created by the cardiology team at the Department of Biomedical Engineering, Brno University of Technology, for the purpose of evaluating photoplethysmographic (PPG) signal quality and estimation of heart rate (HR). The data comprises 48 10-second recordings of PPGs and associated electrocardiographic (ECG) signals used for determination of reference HR. The data were collected from 12 subjects (6 female, 6 male) aged between 21 and 61. PPG data were collected by smartphone Xiaomi Mi9 with sampling frequency of 30 Hz. Reference ECG signals were recorded using a mobile ECG recorder (Bittium Faros 360) with a sampling frequency of 1,000 Hz. Each PPG signal includes annotation of quality created manually by biomedical experts and reference HR. PPG signal quality is indicated binary: 1 indicates good quality for HR estimation, 0 indicates signals where HR cannot be detected reliably, and thus, these signals are unsuitable for further analysis. As the only available database containing PPG signals recorded by smartphone, BUT PPG is a unique tool for the development of smart, user-friendly, cheap, on-the-spot, self-home-monitoring of heart rate with the potential of widespread using.

Bioreactor Co-Cultivation of High Lipid and Carotenoid Producing Yeast Rhodotorula kratochvilovae and Several Microalgae under Stress.

The co-cultivation of red yeasts and microalgae works with the idea of the natural transport of gases. The microalgae produce oxygen, which stimulates yeast growth, while CO2 produced by yeast is beneficial for algae growth. Both microorganisms can then produce lipids. The present pilot study aimed to evaluate the ability of selected microalgae and carotenogenic yeast strains to grow and metabolize in co-culture. The effect of media composition on growth and metabolic activity of red yeast strains was assessed simultaneously with microalgae mixotrophy. Cultivation was transferred from small-scale co-cultivation in Erlenmeyer flasks to aerated bottles with different inoculation ratios and, finally, to a 3L bioreactor. Among red yeasts, the strain R. kratochvilovae CCY 20-2-26 was selected because of the highest biomass production on BBM medium. Glycerol is a more suitable carbon source in the BBM medium and urea was proposed as a compromise. From the tested microalgae, Desmodesmus sp. were found as the most suitable for co-cultivations with R. kratochvilovae. In all co-cultures, linear biomass growth was found (144 h), and the yield was in the range of 8.78-11.12 g/L of dry biomass. Lipids increased to a final value of 29.62-31.61%. The FA profile was quite stable with the UFA portion at about 80%. Around 1.98-2.49 mg/g CDW of carotenoids with torularhodine as the major pigment were produced, ubiquinone production reached 5.41-6.09 mg/g, and ergosterol yield was 6.69 mg/g. Chlorophyll production was very low at 2.11 mg/g. Pilot experiments have confirmed that carotenogenic yeasts and microalgae are capable of symbiotic co-existence with a positive impact om biomass growth and lipid metabolites yields.

Pathologies affect the performance of ECG signals compression.

The performance of ECG signals compression is influenced by many things. However, there is not a single study primarily focused on the possible effects of ECG pathologies on the performance of compression algorithms. This study evaluates whether the pathologies present in ECG signals affect the efficiency and quality of compression. Single-cycle fractal-based compression algorithm and compression algorithm based on combination of wavelet transform and set partitioning in hierarchical trees are used to compress 125 15-leads ECG signals from CSE database. Rhythm and morphology of these signals are newly annotated as physiological or pathological. The compression performance results are statistically evaluated. Using both compression algorithms, physiological signals are compressed with better quality than pathological signals according to 8 and 9 out of 12 quality metrics, respectively. Moreover, it was statistically proven that pathological signals were compressed with lower efficiency than physiological signals. Signals with physiological rhythm and physiological morphology were compressed with the best quality. The worst results reported the group of signals with pathological rhythm and pathological morphology. This study is the first one which deals with effects of ECG pathologies on the performance of compression algorithms. Signal-by-signal rhythm and morphology annotations (physiological/pathological) for the CSE database are newly published.

Main Factors Predicting Nonresponders to Autologous Cell Therapy for Critical Limb Ischemia in Patients With Diabetic Foot.

Autologous cell therapy (ACT) is a new treatment for patients with no-option critical limb ischemia (NO-CLI). We evaluated the factors involved in the nonresponse to ACT in patients with CLI and diabetic foot. Diabetic patients (n = 72) with NO-CLI treated using ACT in our foot clinic over a period of 8 years were divided into responders (n = 57) and nonresponders (n = 15). Nonresponder was defined as an insufficient increase in transcutaneous oxygen pressure by <5 mm Hg, 3 months after ACT. Patient demographics, diabetes duration and treatment, and comorbidities as well as a cellular response to ACT, limb-related factors, and the presence of inherited thrombotic disorders were compared between the 2 groups. The main independent predictors for an impaired response to ACT were heterozygote Leiden mutation (OR 10.5; 95% CI, 1.72-4) and homozygote methylenetetrahydrofolate reductase (MTHFR 677) mutation (OR 3.36; 95% CI, 1.0-14.3) in stepwise logistic regression. Univariate analysis showed that lower mean protein C levels (P = .041) were present in nonresponders compared with responders. In conclusion, the significant predictors of an impaired response to ACT in diabetic patients with NO-CLI were inherited thrombotic disorders.

The Use of Raman Spectroscopy to Monitor Metabolic Changes in Stressed Metschnikowia sp. Yeasts.

Raman spectroscopy is a universal method designed for the analysis of a wide range of physical, chemical and biological systems or various surfaces. This technique is suitable to monitor various components of cells, tissues or microorganisms. The advantages include very fast non-contact and non-destructive analysis and no or minimal need for sample treatment. The yeasts Metschnikowia can be considered as industrially usable producers of pulcherrimin or single-cell lipids, depending on cultivation conditions and external stress. In the present study, Raman spectroscopy was used as an effective tool to identify both pulcherrimin and lipids in single yeast cells. The analysis of pulcherrimin is very demanding; so far, there is no optimal procedure to analyze or identify this pigment. Based on results, the strong dependence of pulcherrimin production on the ferric ion concentration was found with the highest yield in media containing 0.1 g/L iron. Further, production of lipids in Metschnikowia cells was studied at different temperatures and C:N ratios, using Raman spectroscopy to follow fatty acids composition, under different regimes, by monitoring the iodine number. The results of Raman spectroscopy were comparable with the fatty acid analysis obtained by gas chromatography. This study therefore supported use of Raman spectroscopy for biotechnological applications as a simple tool in the identification and analysis both the pulcherrimin and microbial lipids. This method provides a quick and relatively accurate estimation of targeted metabolites with minimal sample modification and allows to monitor metabolic changes over time of cultivation.

Complex study on compression of ECG signals using novel single-cycle fractal-based algorithm and SPIHT.

Compression of ECG signal is essential especially in the area of signal transmission in telemedicine. There exist many compression algorithms which are described in various details, tested on various datasets and their performance is expressed by different ways. There is a lack of standardization in this area. This study points out these drawbacks and presents new compression algorithm which is properly described, tested and objectively compared with other authors. This study serves as an example how the standardization should look like. Single-cycle fractal-based (SCyF) compression algorithm is introduced and tested on 4 different databases-CSE database, MIT-BIH arrhythmia database, High-frequency signal and Brno University of Technology ECG quality database (BUT QDB). SCyF algorithm is always compared with well-known algorithm based on wavelet transform and set partitioning in hierarchical trees in terms of efficiency (2 methods) and quality/distortion of the signal after compression (12 methods). Detail analysis of the results is provided. The results of SCyF compression algorithm reach up to avL = 0.4460 bps and PRDN = 2.8236%.

Real-Time Quality Assessment of Long-Term ECG Signals Recorded by Wearables in Free-Living Conditions.

OBJECTIVE: Nowadays, methods for ECG quality assessment are mostly designed to binary distinguish between good/bad quality of the whole signal. Such classification is not suitable to long-term data collected by wearable devices. In this paper, a novel approach to estimate long-term ECG signal quality is proposed. METHODS: The real-time quality estimation is performed in a local time window by calculation of continuous signal-to-noise ratio (SNR) curve. The layout of the data quality segments is determined by analysis of SNR waveform. It is distinguished between three levels of ECG signal quality: signal suitable for full wave ECG analysis, signal suitable only for QRS detection, and signal unsuitable for further processing. RESULTS: The SNR limits for reliable QRS detection and full ECG waveform analysis are 5 and 18 dB respectively. The method was developed and tested using synthetic data and validated on real data from wearable device. CONCLUSION: The proposed solution is a robust, accurate and computationally efficient algorithm for annotation of ECG signal quality that will facilitate the subsequent tailored analysis of ECG signals recorded in free-living conditions. SIGNIFICANCE: The field of long-term ECG signals self-monitoring by wearable devices is swiftly developing. The analysis of massive amount of collected data is time consuming. It is advantageous to characterize data quality in advance and thereby limit consequent analysis to useable signals.

Advanced P Wave Detection in Ecg Signals During Pathology: Evaluation in Different Arrhythmia Contexts.

Reliable P wave detection is necessary for accurate and automatic electrocardiogram (ECG) analysis. Currently, methods for P wave detection in physiological conditions are well-described and efficient. However, methods for P wave detection during pathology are not generally found in the literature, or their performance is insufficient. This work introduces a novel method, based on a phasor transform, as well as innovative rules that improve P wave detection during pathology. These rules are based on the extraction of a heartbeats' morphological features and knowledge of heart manifestation during both physiological and pathological conditions. To properly evaluate the performance of the proposed algorithm in pathological conditions, a standard database with a sufficient number of reference P wave positions is needed. However, such a database did not exist. Thus, ECG experts annotated 12 chosen pathological records from the MIT-BIH Arrhythmia Database. These annotations are publicly available via Physionet. The algorithm performance was also validated using physiological records from the MIT-BIH Arrhythmia and QT databases. The results for physiological signals were Se = 98.42% and PP = 99.98%, which is comparable to other methods. For pathological signals, the proposed method reached Se = 96.40% and PP = 85.84%, which greatly outperforms other methods. This improvement represents a huge step towards fully automated analysis systems being respected by ECG experts. These systems are necessary, particularly in the area of long-term monitoring.

The Superiority of Removable Contact Splints in the Healing of Diabetic Foot during Postoperative Care.

OBJECTIVE: Off-loading is one of the crucial components of diabetic foot (DF) therapy. However, there remains a paucity of studies on the most suitable off-loading for DF patients under postoperative care. The aim of our study was to evaluate the effect of different protective off-loading devices on healing and postoperative complications in DF patients following limb preservation surgery. METHODS: This observational study comprised 127 DF patients. All enrolled patients had undergone foot surgery and were off-loaded empirically as follows: wheelchair+removable contact splint (RCS) (group R: 29.2%), wheelchair only (group W: 48%), and wheelchair+removable prefabricated device (group WP: 22.8%). We compared the primary (e.g., the number of healed patients, healing time, and duration of antibiotic (ATB) therapy) and secondary outcomes (e.g., number of reamputations and number and duration of rehospitalizations) with regard to the operation regions across all study groups. RESULTS: The lowest number of postoperative complications (number of reamputations: p = 0.028; rehospitalizations: p = 0.0085; and major amputations: p = 0.02) was in group R compared to groups W and WP. There was a strong trend toward a higher percentage of healed patients (78.4% vs. 55.7% and 65.5%; p = 0.068) over a shorter duration (13.7 vs. 16.5 and 20.3 weeks; p = 0.055) in the R group, as well. Furthermore, our subanalysis revealed better primary outcomes in patients operated in the midfoot and better secondary outcomes in patients after forefoot surgery-odds ratios favouring the R group included healing at 2.5 (95% CI, 1.04-6.15; p = 0.037), reamputations at 0.32 (95% CI, 0.12-0.84; p = 0.018), and rehospitalizations at 0.22 (95% CI, 0.08-0.58; p = 0.0013). CONCLUSIONS: This observational study suggests that removable contact splint combined with a wheelchair is better than a wheelchair with or without removable off-loading device for accelerating wound healing after surgical procedures; it also minimises overall postoperative complications, reducing the number of reamputations by up to 77% and the number of rehospitalizations by up to 66%.

Benefits of Acidifying Agents in Local Therapy of Diabetic Foot Ulcers Infected by Pseudomonas sp: A Pilot Study.

Infections caused by Pseudomonas sp are difficult to resolve by antibiotics (ATBs) and local therapy. The aim of our pilot study was to assess the effect of different local agents-particularly acidifying solutions-on the healing of diabetic foot ulcers (DFUs), eradication of pathogens, and economic costs related to DFU therapy. In this case study, we monitored 32 DFU patients infected by Pseudomonas species. Patients were divided into 2 groups according to the local therapy provided: group 1 (n = 15)-modern local treatment; group 2 (n = 17)-acidifying antiseptic solutions. The study groups differed only with regard to ATB usage prior to enrolment in the study (P = .004), but did not differ with regard to age, diabetes control, peripheral arterial disease, or microcirculation status. During the follow-up period, DFUs healed in 20% of cases in group 1, but there were no cases of healing in group 2 (NS). The length of ATB therapy, the number of new osteomyelitis, lower limb amputations, and the changes of DFUs status/proportions did not differ significantly between study groups. Pseudomonas was eradicated in 67% of cases in group 1 and in 65% of cases in group 2. The local treatment given to group 2 patients was associated with lower costs (P < .0001). Conclusion. Acidifying agents had the same effect as modern healing agents on wound healing, the number of amputations, and the eradication of Pseudomonas. Moreover, therapy performed using acidifying solutions proved in our pilot study markedly cheaper.

Endothelial Progenitor Cells Biology in Diabetes Mellitus and Peripheral Arterial Disease and their Therapeutic Potential.

Endothelial progenitors are a population of cells with the inherent capacity to differentiate into mature endothelial cells and proangiogenic paracrine action. These characteristics have led to extensive studies being performed and tested in the treatment of tissue ischemia. The natural course of diabetes mellitus (DM) results in multiple areas of vascular damage. Thus endothelial progenitor cells'(EPCs) beneficial potential is particularly desirable in diabetic patients. In this review, we summarize contemporary knowledge of EPC biology in DM. It has been shown that EPC functions are considerably impaired by DM. The presence of peripheral arterial disease (PAD) seems to further exacerbate the deficiencies of EPCs. However, studies examining EPC counts in PAD and DM observed disparate results, which can be due to a lack of consensus on precise EPC immunotype used in the different studies. Nevertheless, the results of EPC-based autologous cell therapy (ACT) are promising. In addition, EPCs have been shown to bean independent predictor of cardiovascular risk and diabetic foot ulcer healing.

A Comparative Analysis of Methods for Evaluation of ECG Signal Quality after Compression.

The assessment of ECG signal quality after compression is an essential part of the compression process. Compression facilitates the signal archiving, speeds up signal transmission, and reduces the energy consumption. Conversely, lossy compression distorts the signals. Therefore, it is necessary to express the compression performance through both compression efficiency and signal quality. This paper provides an overview of objective algorithms for the assessment of both ECG signal quality after compression and compression efficiency. In this area, there is a lack of standardization, and there is no extensive review as such. 40 methods were tested in terms of their suitability for quality assessment. For this purpose, the whole CSE database was used. The tested signals were compressed using an algorithm based on SPIHT with varying efficiency. As a reference, compressed signals were manually assessed by two experts and classified into three quality groups. Owing to the experts' classification, we determined corresponding ranges of selected quality evaluation methods' values. The suitability of the methods for quality assessment was evaluated based on five criteria. For the assessment of ECG signal quality after compression, we recommend using a combination of these methods: PSim SDNN, QS, SNR1, MSE, PRDN1, MAX, STDERR, and WEDD SWT.