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Abstract

Objective

Colposcopy can be used with Electrical Impedance Spectroscopy (EIS) as an adjunct, to assess the presence of High Grade Cervical Intra-epithelial Neoplasia (CIN2+). This analysis of longitudinal data has used the results from women with a negative colposcopy, in order to see if the initial (index) EIS results were able to predict the women who subsequently developed CIN2+. A further objective was to investigate what tissue structural changes might be reflected in the electrical impedance spectra.

Methods

847 patients were referred with low grade cytologly. EIS measurements were made around the transformation zone of the cervix during colposcopy. Every EIS spectrum was matched to a template representing CIN2+ and the result was positive if the match exceeded a probability index threshold. The colposcopic impression was also recorded. All the women who developed biopsy proven CIN2+ within three years of the index colposcopy were identified.

Results

The median follow-up was 30.5 months. Where both CI and EIS were initially positive, there was an increased prevalence (8.13%) of CIN2+ developing as opposed to 3.45% in the remaining patients (p=0.0159). In addition, if three or more EIS spectra were positive there was a higher prevalence (9.62% as opposed to 3.56% p=0.0132) of CIN2+ at three years. The index spectra recorded from the women who developed CIN2+ showed EIS changes consistent with increases in the extracellular volume and in cell size inhomogeneity.

Conclusion

EIS does offer prognostic information on the risk of CIN2+ developing over the three-year period following the EIS measurements. The changes in EIS spectra are consistent with an increase in cell size diversity as pre-malignancy develops. These changes may be a consequence of increased genetic diversity as neoplasia develops.

Abstract

The electrosurgical unit (ESU) is the most common device in modern surgery for cutting and coagulation of tissues. It produces high-frequency alternating current to prevent the stimulation of muscles and nerves. The commercial ESUs are generally expensive and their output power is uncontrolled. The main objective of the proposed study is to propose an economic ESU with an additional feature of output power regulation using a fuzzy logic controller (FLC) based proportional integral derivative (PID) tuned controller. Unlike the previous studies, the proposed controller is designed in a fully closed-loop control fashion to regulate the output power of the ESU to a fixed value under the consideration of highly dynamic tissue impedance. The performance of the proposed method is tested in the MATLAB/SIMULINK environment. In order to validate the superiority of the proposed method, a comparative analysis with a simple (PID) controller based ESU is presented.

Abstract

Background

Scientific collaboration is more common now than it was before. In many areas of biomedical science, collaborations between researchers with different scientific backgrounds and perspectives have enabled researchers to address complicated questions and solve complex problems.

Particularly, international collaborations and improvements in science and technology have shed light on solving the mechanisms that are involved in the etiology of many rare diseases. Hence, the diagnosis and treatment options have been improved for a number of rare diseases. The collaboration between Near East University DESAM Institute and MAGI Research, Diagnosis and Treatment Center of Genetic and Rare Diseases brought out significant results. Importantly, this collaboration contributed to the rare disease research by the identification of novel rare genetic disease-causing variations commonly in pediatric cases. Consequently, many pediatric unsolved cases have been diagnosed.

The main scope of this article is to emphasize the outcomes of the collaboration between Near East University DESAM Institute and MAGI Research, Diagnosis and Treatment Center of Genetic and Rare Diseases which contributed greatly to the scientific literature by identifying novel rare genetic disease-causing variation.

Abstract

Carbohydrate uptake before physical exercise allows to maintain plasma glucose concentration. Though, foods or beverages containing the same carbohydrate concentration do not produce the same glycemic and insulin responses which are related to their glycemic index (GI). Last, most studies of CHO loading have been conducted with male subjects, with the assumption that the results also apply to female athletes.

Sixteen volunteer amateur athletes, eight men and eight women (age 39.1 ± 7.8 y; VO2max 55,7 ± 11,7 ml/kg/min), were selected and then divided into four groups of four people each one. The trial was divided into several days, one for each group. A carbohydrate source or a placebo (energy 86,5 ± 6,7 kcal; CHO 20,0 g; fat 0,3 ± 0,3 g; protein 0,8 ± 0,8 g) was assigned randomly to each athlete in the group: these supplements differed in the ability to increase blood glucose (banana: high-GI; dried apricots: low-GI; energy gel: mixture of CHO with different blood release), while the placebo was composed of water, sodium cyclamate, sodium saccharin and acesulfame potassium. Three blood samples were taken from each athlete from finger, by glucometer: one before supplementation, one half an hour later – at the start of the run – and one at the end of the exercise.

Physical activity consisted of 40 minutes run at medium-high intensity, corresponding to 82% of maximum heart rate or 70% of VO2max. In order to improve the analysis of the results obtained from the detection of biological samples, a questionnaire was submitted to all participants to know their lifestyle and anthropometric and physiological data.

Results highlighted a different glycemic response between men and women, suggesting the consumption of low-GI food rather than high-GI before physical exercise in order to keep plasma glucose levels constant.

Abstract

Pineapple is an economically important tropical fruit crop, but the lack of adequate planting material limits its productivity. A range of micropropagation protocols has been developed over the years to address this shortfall. Still, the final stage of micropropagation, i.e. acclimatisation, remains a challenge as pineapple plantlets grow very slowly. Several studies have been conducted focusing on this phase and attempting to improve plantlet growth and establishment, which requires tools for the non-destructive evaluation of growth during acclimatisation. This report describes the use of semi-automated and automated image analysis to quantify canopy growth of pineapple plantlets, during five months of acclimatisation. The canopy area progressively increased during acclimatisation, particularly after 90 days. Regression analyses were performed to determine the relationships between the automated image analysis and morphological indicators of growth. The mathematical relationships between estimations of the canopy area and the fresh and dry weights of intact plantlets, middle-aged leaves (D leaves) and roots showed determination coefficients (R2) between 0.84 and 0.92. We propose an appropriate tool for the simple, objective and non-destructive evaluation of pineapple plantlets growth, which can be generally applied for plant phenotyping, to reduce costs and develop streamlined pipelines for the assessment of plant growth.

Abstract

Fluorescent dyes offer a useful method for the measurement of intracellular lipids. They are inexpensive and require simple optical measurement instrumentation, whilst simultaneously providing high throughput application. Nile Red is a hydrophobic, metachromatic dye which has been widely used for detection of intracellular lipids. However, Nile Red fluorescence depends on its concentration, microenvironment polarity, incubation time and, therefore, requires strain specific optimization. Hence, neutral lipids in Chlorella emersonii and Pseudokirchneriella subcapitata cannot be quantified using existing Nile Red methods developed for other microalgae strains and, therefore an optimised procedure for these strains is required. In this method development, the optimal excitation and emission wavelengths were selected based on the solvent used for Nile Red dissolution. The effect of Nile Red concentration, microalgae cell concentration, incubation time on fluorescence intensity was explored and optimised. Quintuplet assay repeats were executed for increased assay robustness for two microalgae strains, Chlorella emersonii and Pseudokirchneriella subcapitata, with protocol reliability confirmed by fluorescence microscopy. In brief, 20% (v/v) DMSO containing 10μg/ml and 5μg/ml Nile red was found to be ideal concentration for neutral lipid estimation in Chlorella emersonii and Pseudokirchneriella subcapitata respectively when an incubation time of 60mins and 40mins at 40°C was used. This optimised Nile Red protocol is a robust, simple and cost-effective method for neutral lipid quantification in Chlorella emersonii and Pseudokirchneriella subcapitata.

Abstract

Undoubtedly, one of the most infectious diseases in the world is tuberculosis. Key factor for tuberculosis control is to prevent possible contagion with rapid diagnosis and effective treatment. The culture method, which it takes several weeks to obtain results, is the gold standard method for laboratory diagnosis of tuberculosis. In order to prevent possible contagion of tuberculosis, diagnosis must be made in short time and treatment should be started as soon as possible. Normally, clinical samples are studied in advanced laboratories designed for this purpose. However, especially after the screening in rural areas, the transmission of the samples to the centers has many negative effects on the clinical material. Therefore, the latest trend molecular techniques in microbiological diagnosis are developing into point of care systems that can be applied in the field without laboratory infrastructure. The major challenge for molecular-based point-of-care tests is the need to store polymerase enzymes and some of the ingredients used in the cold chain. The aim of this study is to increase the resistance of the amplification reaction mixtures by lyophilizing the tuberculosis diagnosis. Lyophilization was performed on Loop-mediated isothermal amplification (LAMP) and Real-time PCR mixtures. For the lyophilization of LAMP and RT-PCR mixtures, two different experimental setups were tried from the literature except for the developed content. Chemicals such as stachyose, trehalose, glycerol and PEG 8000 are widely using as cryoprotectants. As a result, the developed content (0.5% PEG 8000, 2.0 % Stachyose) was determined the best cryoprotectant mixture. Accordingly, amplification mixtures can be produced with the developed lyophilization method and point of care kits can be developed.

Abstract

Significant healthcare disparities resulting from personal wealth, circumstances of birth, education level, and more are internationally prevalent. As such, advances in biomedical science overwhelmingly benefit a minority of the global population. Point-of-Care Testing (POCT) can contribute to societal equilibrium by making medical diagnostics affordable, convenient, and fast. Unfortunately, conventional POCT appears stagnant in terms of achieving significant advances. This is attributed to the high cost and instability associated with conventional biorecognition: primarily antibodies, but nucleic acids, cells, enzymes, and aptamers have also been used. Instead, state-of-the-art biosensor researchers are increasingly leveraging molecularly imprinted polymers (MIPs) for their high selectivity, excellent stability, and amenability to a variety of physical and chemical manipulations. Besides the elimination of conventional bioreceptors, the incorporation of nanomaterials has further improved the sensitivity of biosensors. Herein, modern nanobiosensors employing MIPs for selectivity and nanomaterials for improved transduction are systematically reviewed. First, a brief synopsis of fabrication and wide-spread challenges with selectivity demonstration are presented. Afterward, the discussion turns to an analysis of relevant case studies published in the last five years. The analysis is given through two lenses: MIP-based biosensors employing specific nanomaterials and those adopting particular transduction strategies. Finally, conclusions are presented along with a look to the future through recommendations for advancing the field. It is hoped that this work will accelerate successful efforts in the field, orient new researchers, and contribute to equitable health care for all.

Abstract

Endometriosis is a common condition that affects reproductive-aged women and is characterized by the presence of endo-metrial tissue outside the uterine cavity with nodules and lesions. The study aimed to analyze lifestyles of women affected by endometriosis in relation with their symptoms. In this observational study, 735 Italian women have been interviewed online through a questionnaire structured in two parts. The first part was mainly anamnestic, focused on gathering information about the age, the stage of disease, comorbidities, involved organs, symptomatology, chirurgical treatment, induced menopause. The second part focused on the individual characteristics and lifestyle of the patients such as the body mass index, physical activity, quality of sleep, and the diet. The results showed how a healthy diet and a regular physical activity reduce drastically the symptoms of the patients.

Abstract

Photodynamic therapy (PDT) is a photo chemotherapeutic strategy that is the application of photosensitizing agent and light on disease or tumor site. The aim of this study is to confirm the feasibility for femtosecond (fs) laser for aminolevulinate (ALA) mediated PDT on skin, breast and bladder cancer cells. Also the remarkable aspects of ALA mediated and laser induced PDT with respect to other literally known applications were investigated.

Metastatic melanoma cells SK-MEL30, mammary epithelial carcinoma cells MCF-7 and bladder cancer cells UMUC-3 were treated with ALA and then the cells were irradiated by fs laser at thirty wavelengths in between 230 and 800 nm for 30s and 60s. Anti-cancer effects of ALA phototherapy on different cancer cell lines were determined. Protoporphyrin IX (PpIX) accumulation was visualized by confocal microscopy. The effective PDT wavelengths were applied to evaluate the degree of apoptosis and necrosis in cells.

The viability tests demonstrated that wavelengths 400-440 nm and 600-630 nm were found to decrease the viability on three model cell lines. PDT at 630 nm exerted cell death by necrosis and apoptosis after 30 s and 60 s periods.

This paper confirms that ALA and femtosecond laser mediated PDT may be used together as therapeutic and diagnostic method to target breast, skin and urinary bladder cancer cells. The use of fs laser allows the flexibility for optimization of wavelength for photosensitizing agents.