Machine learning insights into PM2.5 changes during COVID-19 lockdown: LSTM and RF analysis in Mashhad

This study seeks to investigate the impact of COVID-19 lockdown measures on air quality in the city of Mashhad employing two strategies. We initiated our research using basic statistical methods such as paired sample t-tests to compare hourly PM2.5 data in two scenarios: before and during quarantine, and pre- and post-lockdown. This initial analysis provided a broad understanding of potential changes in air quality. Notably, a low reduction of 2.40% in PM2.5 was recorded when compared to air quality prior to the lockdown period. This finding highlights the wide range of factors that impact the levels of particulate matter in urban settings, with the transportation sector often being widely recognized as one of the principal causes of this issue. Nevertheless, throughout the period after the quarantine, a remarkable decrease in air quality was observed characterized by distinct seasonal patterns, in contrast to previous years. This finding demonstrates a significant correlation between changes in human mobility patterns and their influence on the air quality of urban areas. It also emphasizes the need to use air pollution modeling as a fundamental tool to evaluate and understand these linkages to support long-term plans for reducing air pollution. To obtain a more quantitative understanding, we then employed cutting-edge machine learning methods, such as random forest and long short-term memory algorithms, to accurately determine the effect of the lockdown on PM2.5 levels. Our models' results demonstrated remarkable efficacy in assessing the pollutant concentration in Mashhad during lockdown measures. The test set yielded an R-squared value of 0.82 for the long short-term memory network model, whereas the random forest model showed a calculated cross-validation R-squared of 0.78. The required computational cost for training the LSTM and the RF models across all data was 25 min and 3 s, respectively. In summary, through the integration of statistical methods and machine learning, this research attempts to provide a comprehensive understanding of the impact of human interventions on air quality dynamics.

Deep-learning Method for the Prediction of Three-Dimensional Dose Distribution for Left Breast Cancer Conformal Radiation Therapy

AIMS

An increase in the demand of a new generation of radiotherapy planning systems based on learning approaches has been reported. At this stage, the new approach is able to improve the planning speed while saving a reasonable level of plan quality, compared with available planning systems. We believe that new achievements, such as deep-learning models, will be able to review the issue from a different point of view.

MATERIALS AND METHODS

The data of 120 breast cancer patients were used to train and test the three-dimensional U-Res-Net model. The network input was computed tomography images and patients' contouring, while the patients' dose distribution was addressed as the output of the model proposed. The predicted dose distributions, created by the model for 10 test patients, were then compared with corresponding dose distributions calculated by a reliable treatment planning system. In particular, the dice similarity coefficients for different isodose volumes, dose difference and mean absolute errors (MAE) for all voxels inside the body, Dmean, D98%, D50%, D2%, V95% for planning target volume and organs at risk were calculated and were statistically analysed with the paired-samples t-test.

RESULTS

The average dose difference for all patients and voxels in body was 0.60 ± 2.81%. The MAE varied from 3.85 ± 6.65% to 8.06 ± 10.00%. The average MAE for test cases was 5.71 ± 1.19%. The average dice similarity coefficients for isodose volumes was 0.91 ± 0.03. The three-dimensional gamma passing rates with 3 mm/3% criteria varied from 78.99% to 97.58% for planning target volume and organs at risk, respectively.

CONCLUSIONS

The investigation showed that a deep-learning model can be applied to predict the three-dimensional dose distribution with optimal accuracy and precision for patients with left breast cancer. As further study, the model can be extended to predict dose distribution in other cancers.

Global prevalence of urinary tract infection in pregnant mothers: a systematic review and meta-analysis

OBJECTIVE

Urinary tract infection (UTI) is a prevalent infection during pregnancy that can lead to complications for both the mother and the foetus. The objective of this systematic review and meta-analysis is to determine the global prevalence of UTIs (both symptomatic and asymptomatic) during pregnancy, based on previous studies in this area. Furthermore, this study aims to identify any factors that contribute to heterogeneity in the prevalence of UTIs during pregnancy.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

This study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines on August 8, 2022. To conduct the systematic review and meta-analysis, a search was performed using the keywords "urinary tract system", "UTI", "pregnancy", and "gestation" was performed in several databases, including Web of Science (WoS), PubMed, Scopus, ScienceDirect, Embase, and Google Scholar, without a time limit until September 18, 2022. The analysis was performed using a random-effects model, and the heterogeneity of the studies was assessed using the I2 index. The Comprehensive Meta-Analysis software (Version 2) was used for data analysis.

RESULTS

The systematic review and meta-analysis of 27 studies, which included a total of 30,641 pregnant women, showed an overall prevalence of UTI (both symptomatic and asymptomatic) to be 23.9% (95% confidence interval: 16.2-33.8). Meta-regression analysis was conducted to examine the impact of two factors, namely study sample size and study year, on the heterogeneity of the meta-analysis. The results revealed that an increase in sample size, and the study year was associated with a decrease in the prevalence of UTI in pregnant women (P < 0.05).

CONCLUSION

The results of our study indicate a global prevalence of UTI in pregnant women to be 23.9%. Therefore, it is recommended that all pregnant women undergo regular UTI screening tests and receive prompt treatment if diagnosed with UTI. Early detection and treatment of UTI during pregnancy are crucial to prevent complications that may affect the health of both the mother and the foetus.

Synergistic effect of alloying on thermoelectric properties of two-dimensional PdPQ (Q = S, Se)

Hosts of 2D materials exist, yet few allow compositional and structural tailoring as the MQ₂ (M = Mo, W; Q = S, Se) family does, for which various structural superlattices have been synthesized. Using thorough first-principles calculations, we show how bonding hierarchy contributes to the structural resilience of 2D PdPQ and allows for full-range alloying of sulfur and selenium. Within the structural unit of Pd₂P₂Q₂, the covalently-bonded [P₂Q₂]^4- polyanions hold the structure together with their molecular-like P-P bonds while ionically bonded Pd-Qs allow the S/Se substitution. Here, the bonding hierarchy imparts superior electronic and structural features to the PdPQ monolayers. As such, the flat-and-dispersive valence band and the eight degenerate valleys of the conduction band benefit the p-type and n-type thermoelectricity of pristine PdPQ, which can be further enhanced by alloying. The high-entropy alloying synergistically suppresses the lattice heat transport from 75 to 30 W m^-1 K^-1 and increases the band degeneracy of PdPQ monolayers, resulting in an overall improvement in zT. Combining these features, in a naïve approach, results in a large zT approaching two for both p-type and n-type doping. However, accurate fully-fledged electron-phonon calculations rebut this promise, showing that at high temperatures, the increased electron scattering results in a stagnant power factor in the flat-and-dispersive valence band. Using a realistic first-principles scattering, we finally calculate the thermoelectric efficiency of PdPQ (Q = S, Se) and highlight the importance of an accurate estimation of electron relaxation time for thermoelectric predictions.

Sex differences in patients with gastrointestinal stromal tumours: do they exist and does it affect survival?

BACKGROUND

Sex differences in cancer have gained attention in recent years. The role of sex as a prognostic factor in gastrointestinal stromal tumours (GIST) has not been well established. The aim of this research was to elucidate potential sex differences in GIST patients and the influence of sex on disease-specific survival (DSS).

METHODS

A review of the literature was carried out to obtain an overview of all literature with sex as a covariate on GIST survival analyses. Furthermore, in the Dutch GIST Registry, GIST characteristics between males and females were compared and the influence of sex on DSS was analysed.

RESULTS

A total of 118 articles from the review of the literature met our selection criteria; 58% of the articles found no sex difference in survival and 42% did find a sex difference. All differences favoured female patients, although there was substantial overlap of individual patients in the various reported groups. The Dutch GIST Registry cohort consisted of 1425 patients (46% female). Compared with female patients, male patients had larger tumours (mean 9.0 cm versus 7.9 cm) and higher mitotic rates (34.4% versus 28.0% >5 mitoses/5 mm²). GIST in males was more often metastasized at diagnosis (21.3% versus 13.7%) and incurable (38.5% versus 31.0%). Male patients less often received surgery of the primary tumour (71.7% versus 78.9%), but did experience more tumour ruptures (18.2% versus 13.3%). Male patients had a worse DSS than females. This was not statistically significant when corrected for differences in GIST characteristics.

CONCLUSIONS

In case of sex differences in GIST in the literature, male patients have a worse outcome. In our Dutch GIST cohort a similar finding was made, but sex was shown not to be an independent factor. Male patients more often had aggressive GISTs, with larger tumours, higher mitotic rates, more tumour ruptures, and metastases, which could explain the sex differences in DSS.

Microstructural examination and mechanical characterization of Ti/HA and Ti/SiO2 functionally graded materials fabricated at different loading rates

Functionally graded material (FGM) is a heterogeneous composite material that consists of two or more constituent phases with continuous changes in the microstructure from one material to another with adjustable through thickness properties. FGMs are utilized in medical applications, such as dental implants, due to their excellent mechanical and tribological properties. In this study, the powder metallurgy method (PMM) is used to produce Titanum/Hydroxyapatite (Ti/HA) and Titanum/Silicon dioxide (Ti/SiO2) FGM samples. A new designed blender is employed to mix the particles constituting the FGM samples. The mixed particles are then compacted at different strain rates from quasi static loading, using a universal testing apparatus, to dynamic loadings, using a drop hammer and a split Hopkinson bar. The effect of strain rate on mechanical properties and microstructure of specimens is studied by conducting various tests such as indentation and compression tests and by microstructural examinations using scanning electron microscopy (SEM). The results showed that the relative density of fabricated specimens was increased with the increase of the strain rate. The highest relative density for the Ti/HA composite was achieved for the specimens produced by the split Hopkinson bar. For both of Ti/HA and Ti/SiO2 FGMs the maximum indentation force and indentation energy, obtained from the load-penetration depth curve, and the ultimate strength, obtained from the compressive stress-strain curve, were increased with the increase in strain rate. The results also indicated that the increase in volume fraction of reinforcing ceramic particles (HA or SiO2) led to the decrease of the maximum indentation force and indentation energy.

Efficacy of COVID-19 vaccines by race and ethnicity

OBJECTIVES

Vaccine uptake amongst ethnic minority populations has been persistently lower, which may be because of socio-economic factors such as health literacy and health insurance status. This review aimed to assess to what extent COVID-19 clinical trials have considered the impact of race and ethnicity on COVID-19 vaccine safety and efficacy.

STUDY DESIGN

This was a systematic review.

METHODS

Data regarding ethnicity in COVID-19 vaccine clinical trials were systematically reviewed according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines in this systematic review, which ran from inception until June 2021. Three international databases, PubMed, Scopus and Web of Science, were used to conduct systematic article searches. Only two studies reported vaccine efficacy among ethnic minority groups.

RESULTS

The efficacy of the mRNA-1273 vaccine was confirmed to be 95% in Caucasians and 97.5% in 'people of colour' in a study by Baden et al. In another study by Polack et al., BNT162b2 mRNA vaccine efficacy was reported to be 95.2% in Caucasians, 100% in Afro-Caribbean or African Americans, 94.2% in Hispanic or Latinx and 95.4% in non-Hispanic, non-Latinx people.

CONCLUSIONS

Given the highly differing effect of COVID-19 on the Afro-Caribbean, Hispanic and South Asian populations, it is imperative for COVID-19 vaccine clinical trials to thoroughly assess the safety and efficacy of vaccines in different ethnicities and, if necessary, develop ethnicity-specific protocols, which can minimise the disproportionate effect of COVID-19 on ethnic minority populations.

Recovery of olfactory and gustatory dysfunctions in coronavirus disease 2019 patients: a prospective cohort study

OBJECTIVE

This study aimed to determine the association of some demographic and clinical factors with recovery from olfactory and gustatory dysfunction in coronavirus disease 2019 patients in Iran.

METHODS

This prospective cohort study was performed on 242 coronavirus disease 2019 patients with olfactory and gustatory dysfunction. The time from onset to recovery for olfactory and gustatory dysfunction was estimated by the Kaplan-Meier estimator.

RESULTS

After six months, 239 patients (98.8 per cent) had completely recovered from olfactory dysfunction. Olfactory and gustatory dysfunction symptoms resolved in 80.99 per cent and 83.56 per cent of the patients, respectively, within the first 30 days of symptom onset. Mean recovery time for olfactory dysfunction (35.07 ± 4.25 days) was significantly longer in those infected during the first epidemic wave compared with those infected during the second wave (21.65 ± 2.05 days) (p = 0.004). A similar pattern in recovery time was observed for cases of gustatory dysfunction (p = 0.005).

CONCLUSION

The recovery rate for coronavirus disease 2019 related olfactory and gustatory dysfunction is high within the first month of symptom onset.

Continuous Scoring of Depression from EEG Signals via a Hybrid of Convolutional Neural Networks

Depression score is traditionally determined by taking the Beck depression inventory (BDI) test, which is a qualitative questionnaire. Quantitative scoring of depression has also been achieved by analyzing and classifying pre-recorded electroencephalography (EEG) signals. Here, we go one step further and apply raw EEG signals to a proposed hybrid convolutional and temporal-convolutional neural network (CNN-TCN) to continuously estimate the BDI score. In this research, the EEG signals of 119 individuals are captured by 64 scalp electrodes through successive eyes-closed and eyes-open intervals. Moreover, all the subjects take the BDI test and their scores are determined. The proposed CNN-TCN provides mean squared error (MSE) of 5.64±1.6 and mean absolute error (MAE) of 1.73±0.27 for eyes-open state and also provides MSE of 9.53±2.94 and MAE of 2.32±0.35 for the eyes-closed state, which significantly surpasses state-of-the-art deep network methods. In another approach, conventional EEG features are elicited from the EEG signals in successive frames and apply them to the proposed CNN-TCN in conjunction with known statistical regression methods. Our method provides MSE of 10.81±5.14 and MAE of 2.41±0.59 that statistically outperform the statistical regression methods. Moreover, the results with raw EEG are significantly better than those with EEG features.

Investigating the relationship between low back pain and quality of life in emergency medical personnel and the role of demographic variables in this regard

Introduction: Back pain is one of the most important occupational problems among health care workers that have detrimental effects on their personal and professional life. Therefore, this study aimed to investigate the relationship between low back pain and quality of life in prehospital emergency staff and the role of demographic variables in this regard. Materials and Methods: This is a descriptive correlational study. The population was a prehospital emergency staff that entered to study by using the census method at 2020. Data gathering instruments were demographic characteristics, low back pain, and quality of life questionnaires. Data were entered into SPSS 22 and were analyzed using descriptive and analytical statistics. Results: The results showed that the related to the low back pain score of emergency medical technicians was 51.34± 4.149, which is high. In addition, the quality of life mean and standard deviation was 30.35± 4.851, which shows a low level. There is a significant relationship between back pain and quality of life (p = 0.001, R = 0.723). Conclusion: Low back pain is so common among emergency medical personnel that the issue may affect a person's life and work and creates many problems in terms of personal, family, socially, economically, and professionally, which reduce their quality of life.

Health promotion through digital means: Refugee women using video and social media in times of COVID-19

Background

Forced migration is particularly hard on women and families. On arrival in host countries, living conditions (e. g. accommodation in camps) and various restrictions connected with the process of seeking asylum severely restrict women's abilities to care for themselves and their families. Gender-based violence is just one of many problems. These problems are exacerbated during the COVID-19 pandemic.

Methods

As part of the EMPOW project at the study site in Hannover, Germany, community partners who are female refugees themselves, are committed to improving the health of other refugee women and families. To pursue this aim, a digital network was established using social media. Short videos were created in Farsi and Arabic addressing various aspects relevant to the health of refugee women and families. These include: a) information on hygiene and how to wear a mask to reduce the spread of Corona, b) activities during COVID related lockdown phases (e.g. games to play with children indoors and gymnastics and sports for adults), and c) further questions and answers on general health and health care.

Results

More than 80 women have joined the digital network within a few months. The videos are distributed and discussed using WhatsApp groups. The community partners collect health related questions from the participating refugee women, which are then answered by a medical doctor in Farsi. The groups provide an opportunity for mutual exchange and advice regarding women's health and the wellbeing of families.

Conclusions

Digital means including short, self-made videos and social media such as WhatsApp groups are valuable means for participatory health promotion with refugee women. Limitations of the digital format are discussed.

Main messages

Refugee women can be reached via social media messages and short video clips.

Peer-based health promotion holds great value for women and families affected by forced migration.

Future Study Of Fire Disaster Risk In Iran Using A Scenario Planning Approach

Fire disasters are one of the most common technological disasters in Iran. These disasters have killed many people and resulted in significant economic loss. The "Plasco" building fire in 2017 is one example of these catastrophic disasters, when most of Iran was affected by its tragic news. Regarding the increasing number of risk factors for fire disasters, we aimed to study future scenarios for such disasters in the country. The present study is a futuristic study with an exploratory approach that uses an intuitive logic scenario development approach. We used document analysis, semi-structured interviews, and the Delphi technique to identify driving forces and develop scenario stories, and finally those scenario stories were validated. In the document analysis phase, 22 documents were identified and analysed. After collecting information related to documents and analysing ten interviews, 41 of the driving forces were identified. By drawing the scenario matrix, four alternative scenarios for the future of fire disasters were developed. Two dimensions for scenario development were the correct application of fire prevention laws and access to driving technologies. Policymakers can concentrate on these key factors for best planning in the mitigation of fire disasters. In addition, studying scenarios can help managers and officials to better develop strategic plans for disaster risk reduction.

Dementia-Friendly Design: A Set of Design Criteria and Design Typologies Supporting Wayfinding

OBJECTIVES, PURPOSE, OR AIM

This study aims to gain insights into the implementation of theoretical knowledge on dementia-friendly design into practice to (1) identify key design criteria stimulating spatial orientation and wayfinding for seniors with dementia and (2) determine the optimal design for this purpose.

BACKGROUND

Spatial orientation problems of seniors with dementia can be counteracted by the design of the physical environment of inpatient care facilities. Research has been conducted about design features supporting wayfinding skills for this target group, however, not on their implementation.

METHODS

Fourteen floor plans of the living group of built projects have been evaluated on 14 design criteria supporting wayfinding skills for the target group and measurable in floor plans by the performance of a comparative floorplan analysis and multicriteria assessment.

RESULTS

Although one third of the evaluated design criteria are properly implemented, all floor plans of the selected projects had some gaps in fulfilling all design criteria. Five typological floor plans-based on the circulation systems of the cases-were distinguished: one straight corridor structured by two walls, one corridor with corners, two corridors separated from each other by the living room, a continuous loop corridor, and a corridor framed by a wall and interior elements (e.g., cabinets). The majority of the cases was based on a linear system with one straight corridor.

CONCLUSIONS

Based on this study, three of the five discovered typological floor plans work well for stimulating wayfinding. Furthermore, special attention need to be given to the configuration of the floor plans, shape, and daylight in the corridor.

Nanoclay Migration and the Rheological Response of PBAT/LDPE Blends

Blends of a poly(butylene adipate-co-terephthalate) (PBAT) and a low density polyethylene (LDPE) (80 wt%/20 wt%) were prepared through a twin screw extruder while incorporating 3 wt% Cloisite 30B (C30B) nanoclay that possessed a much higher affinity with PBAT. The blends were processed through three melt mixing strategies: ( i) direct mixing of all three components, (ii) mixing C30B and PBAT followed by mixing with LDPE, and (iii) mixing C30B and LDPE followed by mixing with PBAT. The rheological properties of each system were determined in small amplitude oscillatory shear (SAOS) experiments. The migration of C30B nanoparticles from the LDPE minor phase towards the PBAT matrix was then monitored in the blend nanocomposites prepared through strategy (iii) via SAOS time sweep experiments. It was firstly understood that the C30B migration could be detected during time sweep SAOS experiments. The migration time was observed to be frequency dependent due to the smaller length scales probed at larger frequencies. Such migration occurred even faster when the SAOS time sweep experiments were conducted at a higher temperature due to the viscosity reduction.

Prevalence of foot varicose veins in hairdressers and some related factors in Gonabad

Introduction: Physical postures at work and occupational conditions are among the important risk factors that increase the prevalence of varicose veins. These include prolonged standing and tedious postures that are unavoidable in the hairdressing profession. This study aimed to investigate the relationship between the prevalence of foot varicose veins and occupational and demographic factors in hairdressers. Materials and Methods: This cross-sectional-correlational study was conducted on 90 hairdressers in Gonabad in 2015. The participants were selected using a random method. After completing the demographic information questionnaire, the samples were examined according to CEAP criteria (clinical findings, etiology, anatomical findings, and pathophysiology). The collected data were analyzed using Chi-square, Fisher, and independent t-tests using SPSS software version 20 at a significance level of p <0.05. Results: Out of 90 patients, 45 were male, and 45 were female, and (77.8%) had an average working time of more than 6 hours. Most of the men (51.1%) and women (53.3%) had varicose veins of the lower extremities of both limbs. The relationship between varicose veins of hairdressers and education (P = 0.031), work experience (P = 0.043), regular exercise (p = 0.012), smoking (P = 0.009) was significant. Conclusion: The present study results indicate the high prevalence of lower limb varicose veins in hairdressers. This disorder causes many mental and physical disorders and ultimately affects the individual's work efficiency, so controlling risk factors and preventing this complication in hairdressers seems necessary.

Molecular survey of aminoglycoside-resistant Acinetobacter baumannii isolated from tertiary hospitals in Qazvin, Iran

Aminoglycoside-modifying enzymes (AMEs) and 16S rRNA methylases (16S RMTase) are two main resistance mechanisms against aminoglycosides. This study aimed to evaluate the frequency of AMEs and 16S rRNA methylase genes among aminoglycoside non-susceptible Acinetobacter baumannii isolates and to assess their clonal relationship using repetitive extragenic palindromic-PCR (rep-PCR). In this cross-sectional study, a total of 192 A. baumannii isolates were collected from the patients hospitalized in Qazvin, Iran (January 2016 to January 2018). Identification of isolates was performed by standard laboratory methods and API 20E strips. Antimicrobial susceptibility was determined by Kirby–Bauer method followed by examination of the genes encoding the AMEs and 16S RMTase by PCR and sequencing methods. The clonal relationship of isolates was carried out by rep-PCR. In total, 98.4% of isolates were non-susceptible to aminoglycosides, 98.4%, 97.9% and 83.9% of isolates were found to be non-susceptible against gentamicin, tobramycin and amikacin, respectively. The frequencies of aph(3′)-VI, aac(6′)-Ib, aac(3)-II, aph(3′)-Ia and armA genes were 59.3%, 39.2%, 39.2%, 31.7% and 69.8%, respectively, either alone or in combination. Rep-PCR results showed that the aminoglycoside non-susceptible isolates belonged to three distinct clones: A (79.4%), B (17.5%) and C (3.2%). The findings of this study showed a high frequency for AMEs with the emergence of armA genes among the aminoglycoside non-susceptible A. baumannii isolates. Rational administration of aminoglycosides as well as using an appropriate infection control policy may reduce the presence of resistance to antibiotics in medical centres.

•

Little is known regarding carbapenem resistance mechanisms in A. baumannii in our region.

•

More than 85% of our isolates were non-susceptible to carbapenems in Qazvin hospitals, Iran.

•

bla_OXA-23, bla_OXA-24, bla_IMP-1, and bla_VIM-1 genes is established in carbapenem resistant A. baumannii isolates.

•

Clonal distribution of carbapenem resistant A. baumannii was demonstrated in investigated hospital settings.

Ocular toxicity assessment of nanoemulsion in-situ gel formulation of fluconazole

PURPOSE

Fluconazole is an effective anti-fungal drug. Due to the limitations of fluconazole, such as poor water solubility and consequently low ocular bioavailability, an optimized fluconazole nanoemulsion in-situ gel formulation (temperature-sensitive) was developed.

METHODS AND MATERIALS

To verify formulation's safety for ophthalmic use, preparation was tested for potential ocular toxicity using a cell viability assay on retinal cells. The hen's egg test-chorioallantoic membrane (HET-CAM), as a borderline test between in vivo and in vitro techniques, was chosen for investigating the irritation potential of the formulation. HET-CAM test was done by adding the formulation directly to the CAM surface and monitoring the vessels visually in terms of irritation reactions. Eye tolerance was determined using the modified Draize test.

RESULTS

Viability assay on retinal cells displayed that fluconazole nanoemulsion in-situ gel formulation was non-toxic and can be safely used in the eye at concentrations of 0.1% and 0.5%. HET-CAM and Draize tests revealed that optimized formulation of fluconazole did not result in any irritation and was considered non-irritant and well-tolerated for ocular use.

CONCLUSION

Regarding to the findings of the three mentioned methods, fluconazole nanoemulsion in-situ gel formulation is harmless and as a proper and safe alternative, can be considered for ocular delivery of fluconazole in the future.

Performance of a linear accelerator couch positioning quality control task using an electronic portal imaging device

Short and semi-automated quality assurance (QA) programs are becoming one of the most popular and highly demanding tasks in radiotherapy. The current research investigates the accuracy of a four degrees of freedom (4DoF) medical linear accelerator couch positioning with a fast and accurate method based on images acquired using an electronic portal imaging device (EPID). An accurate EPID QA phantom and a proper in-house code were used. A Siemens medical linear accelerator equipped with an a-Si EPID was used to acquire portal images. For verifying the mechanical performance of the EPID positioning, EPID sensitivity, and accuracy of the code response from the image processing point of view were investigated. To characterize the results, three deviations in the phantom positioning were deliberately created. The translational and rotational displacements of the treatment couch were then evaluated. The loading effect on the treatment couch was then investigated. The results of prerequisite tests, including the mechanical performance of the EPID, and the sensitivity and accuracy of the recognition codes, were assessed. The results were found to be within the tolerance range reported at AAPM TG-142. The mean deviations of the tests between expected and measured displacements by 4DoF treatment couch were found to be 0.13° ± 0.11°, 0.12 ± 0.17 mm, 0.17 ± 0.13 mm, and 0.04 ± 0.09 mm for rotational, longitudinal, lateral, and vertical shifts, respectively. The results showed that the proposed method is a reliable and fast approach to find the uncertainties occurring intreatment couch positioning.

Identification of polcalcin as a novel allergen of Amaranthus retroflexus pollen

INTRODUCTION

Amaranthus retroflexus (Redroot Pigweed) is one of the main sources of allergenic pollens in temperate areas. Polcalcin is a well-known panallergen involved in cross-reactivity between different plants. The aim of this study was the molecular cloning and expression of polcalcin, as well as evaluating its IgE-reactivity with A. retroflexus sensitive patients' sera.

METHODS

Allergenic extract was prepared from A. retroflexus pollen and the IgE-reactivity profile was determined by ELISA and immunoblotting using sera from twenty A. retroflexus sensitive patients. Polcalcin-coding sequence was amplified by conventional PCR method and the product was inserted into pET-21b(+) vector. The recombinant protein was expressed in E. coli BL21 and purified by metal affinity chromatography. The IgE-binding capability of the recombinant protein was analyzed by ELISA and immunoblotting assays, and compared with crude extract.

RESULTS

Of 20 skin prick test positive patients, 17 patients were positive in IgE-specific ELISA. Western blotting confirmed that approximately 53% of ELISA positive patients reacted with 10kDa protein in crude extract. The A. retroflexus polcalcin gene, encoding to 80 amino acid residues was cloned and expressed as a soluble protein and designated as Ama r 3. The recombinant polcalcin showed rather identical IgE-reactivity in ELISA and western blotting with 10kDa protein in crude extract. These results were confirmed by inhibition methods, too.

CONCLUSION

The recombinant form of A. retroflexus polcalcin (Ama r 3) could be easily produced in E. coli in a soluble form and shows rather similar IgE-reactivity with its natural counterpart.

Evaluation of Breast Cancer Radiation Therapy Techniques in Outfield Organs of Rando Phantom with Thermoluminescence Dosimeter

BACKGROUND

Given the importance of scattered and low doses in secondary cancer caused by radiation treatment, the point dose of critical organs, which were not subjected to radiation treatment in breast cancer radiotherapy, was measured.

OBJECTIVE

The purpose of this study is to evaluate the peripheral dose in two techniques of breast cancer radiotherapy with two energies.

MATERIAL AND METHODS

Eight different plans in two techniques (conventional and conformal) and two photon energies (6 and 15 MeV) were applied to Rando Alderson Phantom's DICOM images. Nine organs were contoured in the treatment planning system and specified on the phantom. To measure the photon dose, forty-eight thermoluminescence dosimeters (MTS700) were positioned in special places on the above nine organs and plans were applied to Rando phantom with Elekta presice linac. To obtain approximately the same dose distribution in the clinical organ volume, a wedge was used on planes with an energy of 6 MeV photon.

RESULTS

Point doses in critical organs with 8 different plans demonstrated that scattering in low-energy photon is greater than high-energy photon. In contrast, neutron contamination in high-energy photon is not negligible. Using the wedge and shield impose greater scattering and neutron contamination on patients with low-and high-energy photon, respectively.

CONCLUSION

Deciding on techniques and energies required for preparing an acceptable treatment plan in terms of scattering and neutron contamination is a key issue that may affect the probability of secondary cancer in a patient.

Impact of comorbidity on disease characteristics, treatment intent and outcome in diffuse large B-cell lymphoma: a Swedish lymphoma register study

BACKGROUND

Comorbidity impacts overall survival amongst patients with diffuse large B-cell lymphoma (DLBCL). However, associations of comorbidity with lymphoma characteristics, treatment selection and lymphoma-specific mortality are less well known.

OBJECTIVE

To examine the impact of comorbidity on DLBCL characteristics, treatment intent and cause of death.

METHODS

We identified 3905 adult patients diagnosed with DLBCL 2007-2013 through the Swedish Lymphoma Register. We assessed comorbid disease history according to the Charlson comorbidity index (CCI). Comorbidity data and causes of death were collected through register linkage. Associations were estimated using multinomial regression and flexible parametric survival models.

RESULTS

Overall, 45% of the patients (n = 1737) had a history of at least one comorbidity at DLBCL diagnosis (cardiovascular disease, diabetes and solid cancer were most frequent), and 997 (26%) had a CCI score of ≥2. The relative probability of presenting with poor performance status (PS > 2) was higher amongst comorbid patients [Relative Risk Ratio (RRR)_PS>2 : 2.02, 95% CI: 1.63-2.51]. Comorbid patients had a substantially lower relative probability of receiving curative treatment (RRR: 0.48, 95% CI: 0.38-0.61). Amongst all patients, CCI ≥ 1 was associated with a significantly increased risk of all-cause and lymphoma-specific death after adjustments. Amongst patients selected for curative treatment, comorbidity was associated with an increased risk of all-cause death (HR_CCI>1 : 1.54, 95% CI: 1.32-1.80), but not with lymphoma-specific death (HR_CCI>1 : 1.05, 95% CI: 0.86-1.28).

CONCLUSION

Comorbidity is associated with inferior DLBCL outcome, mainly due to a lower likelihood of receiving treatment with curative intent. Possibly, more comorbid DLBCL patients could be treated with curative intent if comorbid conditions were optimized in parallel.

Selective and metal-free epoxidation of terminal alkenes by heterogeneous polydioxirane in mild conditions

Polydioxirane (PDOX) was prepared by the treatment of polysalicylaldehyde with Oxone and was found as a selective, highly efficient and heterogeneous reagent for epoxidation of alkenes which can be successfully isolated. This work also introduced a simpler, safer and milder way for epoxidation of alkenes with dioxirane groups than before. PDOX can be simply recovered from the reaction mixture by plain filtration and reused for eight runs without significant reactivity loss.

Down-regulation of CatSper 1 and CatSper 2 genes by lead and mercury

In the study of the expression of CatSper genes, consideration of the effects of environmental metal toxicity is very important. Therefore, in this study, the effects of lead acetate and mercury chloride exposure on expression of CatSper genes, sperm parameters, histology of testis and prooxidant antioxidant balance (PAB) values of serum were investigated. A total of 28 mice was divided into four groups. The control group did not receive injections. The sham group received normal saline intraperitoneally. Lead and mercury groups were injected 60 and 1.25 mg/kg/daily lead acetate and mercury chloride respectively intraperitoneally for 2 weeks. After 35 days, the sperm analysis and histology of left testis were performed. In addition, serum was obtained to measure the PAB values. The right testis was used for molecular analysis of real-time PCR. Administration with either lead acetate or mercury caused significant damage to the seminiferous tubules as well as a reduction in sperm parameters compared to the control group. The relative expression of CatSper 1 and CatSper 2 in the lead group was lower than that of the control group (-0.01 ± 0.24, -0.007 ± 0.52 vs. 1 ± 0.50, P = 0.34). The relative expression of CatSper 1 and CatSper 2 was significantly lower in the mercury group compared to the control ones (-0.24 ± 2.28, -4.49 ± 4.86 vs. 1 ± 0.50, P = 0.21). PAB values significantly increased in lead or mercury exposed- mice compared to the control ones (0.93 ± 0.17, 1.54 ± 0.17 vs. 0.51 ± 0.11; P ≤ 0.000). The results of this study showed that administration with either lead acetate or mercury chloride caused degenerative damage in seminiferous tubules and reduction in sperm quality and expression of CatSper 1, 2 genes in mice. Therefore, it is possible in infertile men who have had exposure to lead acetate or mercury chloride. Owing to structural similarities, these metals are substitutes for calcium ions and have effects on calcium channels. These cause immobility in sperm by blocking CatSper-specific calcium channels. However, more studies are required to elucidate the mechanism underlying the impact of different doses of heavy metals on CatSper genes expression.

Protective Effects of IMOD and Cimetidine against Radiation-induced Cellular Damage

Radiation damage is to a large extent caused by overproduction of reactive oxygen species (ROS). Radioprotectors are agents or substances that reduce the effects of radiation in healthy normal tissues while maintaining the sensitivity to radiation damage in tumor cells. Radioprotectors are agents or substances that reduce the effects of radiation in healthy normal tissues while maintaining the sensitivity to radiation damage in tumor cells Cimetidine was found more effective when used in vivo; this effect might be due to the augmentation of the presence of Sulphur atom in the compound which is ýimportant for their scavenging activity. Recently, a new herbal-based medicine with immunomodulatory capacities, Setarud (IMOD), was introduced as an additional therapy in various inflammatory diseases and HIV infection. IMOD is a mixture of herbal extracts enriched with selenium. Selenium confers protection by inducing or activating cellular free-radical scavenging systems and by enhancing peroxide breakdown. This article suggests that nontoxic amount of IMOD and cimetidine have radioprotective properties and could reduce cytotoxic effects of radiation.

3D investigation of dynamic behavior and sensitivity analysis of the parameters of spherical biological particles in the first phase of AFM-based manipulations with the consideration of humidity effect

The imaging and manipulation tools being the same in an AFM has necessitated the modeling and simulation of the AFM-based manipulation processes. In earlier studies, the dynamic behavior of biological particles in the course of manipulation has been modeled and simulated two-dimensionally. Now, with the advancements made in the modeling techniques, a 3D model of the manipulation of biological particles is more accurate than its 2D counterpart. In this paper, the effect of humidity has been taken into consideration in the three-dimensional modeling of the manipulation. By employing this model, the equations for the motion modes of particles (sliding, rolling, and spinning) at the onset of movement have been derived and the critical force magnitude has been obtained. In order to reduce the potential damage to the manipulated biological particle, the maximum radius of the tip has been determined. The effective parameters in this process have been extracted by performing sensitivity analysis using the Sobol method. In comparison to the results obtained for a dry environment, the results obtained by simulating the manipulation of a yeast particle in a wet environment shows that the critical force for the onset of particle movement diminishes by considering the moisture effect (high humidity levels). The parameters influencing the magnitude of the critical force include the particle radius, particle material, surface energy of the chosen substrate, amount of preload and the contact angle. Also, the results of the performed sensitivity analysis indicate a very high influence of particle radius on the critical manipulation force and a very low impact of cantilever width on the critical force.

The effect of electro-acupuncture on pro-oxidant antioxidant balance values in overweight and obese subjects: a randomized controlled trial study

Objective To undertake a randomized controlled trial in 196 obese subjects to examine the effect of electro-acupuncture on serum pro-oxidant antioxidant balance (PAB) values. Methods Subjects received authentic acupuncture (cases) or sham acupuncture (controls) for 6 weeks in combination with a low-calorie diet. In the following 6 weeks, they received the low-calorie diet alone. Serum PAB was measured at baseline, and 6 and 12 weeks later. Results We found that serum PAB values decreased significantly in the group receiving the authentic acupuncture compared to the sham treatment (p<0.001) at week 6, and whilst serum PAB increased significantly (p<0.05) in the second phase of the study, a significant difference between two groups remained at 12 weeks (p<0.05). Conclusions Electro-acupuncture in combination with a low-calorie diet was more effective at reducing serum PAB values in obese subjects compared to diet alone. Further work is required to determine the mechanism by which electro-acupuncture has this effect.

Retinal nerve fibre layer thickness is reduced in metabolic syndrome

AIMS

To investigate retinal nerve fibre layer (RNFL) thickness in people with metabolic syndrome (MetS) and healthy controls.

METHODS

A cross-sectional study was performed from March 2014 to January 2016. All participants underwent anthropometric and serological biochemical measurements, ophthalmological examination, and spectral-domain optical coherence tomography (SD-OCT). Individuals with elevated intraocular pressure, glaucoma, diabetic retinopathy and other ocular disorders were excluded. T-test, Chi square and general linear models were used to analyse the data.

RESULTS

In total, 278 eyes from 139 participants were investigated [median (interquartile range) age: 37 (32-43) years]. RNFL thickness was lower in the nasal superior (107.8 ± 19.5μm) and temporal superior (135.7 ± 18.9μm) sectors in MetS group compared with the control group (114.6 ± 22.4 μm, P = 0.013 and 140.7 ± 18.2 μm, P = 0.027, respectively). After multiple adjustments for age, gender and the side of the examined [right (OD)/left (OS)] eye, MetS was independently associated with a lower RFNL thickness in the nasal superior (β = 0.20, P = 0.009) and temporal superior (β = 0.14, P = 0.048) sectors. RNFL thickness was significantly reduced in participants with higher numbers of metabolic abnormalities, independent of age, gender and the side of the examined eye (P = 0.043).

CONCLUSION

Our findings demonstrate that MetS is independently associated with reduced RNFL thickness, suggesting that neurodegeneration is implicated in pathogenesis of MetS.

THE EFFECT OF TESTOSTERONE AND VOLUNTARY EXERCISE, ALONE OR TOGETHER, ON miRNA-126 EXPRESSION CHANGES IN HEART OF DIABETIC RATS

Methods

Ninety Wistar male rats were used in this study. Type 1 diabetes was induced by i.p injection of 50 mg/kg of streptozotocin in all animals. After 42 days of treatment with testosterone (2mg/kg/day) or voluntary exercise alone or in combination, the heart of the rats has been removed and MicroRNA was extracted from the heart using miRCURYTM RNA isolation kit.

Results

Our results showed that either testosterone or exercise increased miRNA-126 expression levels in the heart of diabetic rats. Treatment of diabetic rats with testosterone and exercise at the same time had a synergistic effect on miRNA-126 levels in the heart. Furthermore, in castrated diabetes group, miRNA-126 levels were significantly decreased in heart, whereas either testosterone treatment or exercise training enhanced expression of this miRNA. Also, simultaneous treatment of castrated diabetic rats with testosterone and exercise had an additive effect on miRNA-126 expression levels.

Conclusion

This study showed that testosterone and exercise promote an increase in the expression of miRNA-126 in the heart tissue and this may be related to cardiac angiogenesis. These results may indicate that testosterone and exercise can help to prevent progression of diabetic cardiomyopathy due to impaired angiogenesis in the heart.

Protective effect of crocin and voluntary exercise against oxidative stress in the heart of high-fat diet-induced type 2 diabetic rats

Background Oxidative stress plays a critical role in the pathogenesis and progression of type 2 diabetes and diabetic-associated cardiovascular complications. This study investigated the impact of crocin combined with voluntary exercise on heart oxidative stress indicator in high-fat diet-induced type 2 diabetic rats. Materials and methods Rats were divided into four groups: diabetes, diabetic-crocin, diabetic-voluntary exercise, diabetic-crocin-voluntary exercise. Type 2 diabetes was induced by high-fat diet (4 weeks) and injection of streptozotocin (intraperitoneally, 35 mg/kg). Animals received crocin orally (50 mg/kg); voluntary exercise was performed alone or combined with crocin treatment for 8 weeks. Finally, malondialdehyde (MDA), activity of antioxidant enzymes, superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) were measured spectrophotometrically. Results Treatment of diabetic rats with crocin and exercise significantly decreased the levels of MDA (p < 0.001) and increased the activity of SOD, GPx, and CAT compared with the untreated diabetic group. In addition, combination of exercise and crocin amplified their effect on antioxidant levels in the heart tissue of type 2 diabetic rats. Conclusion We suggest that a combination of crocin with voluntary exercise treatment may cause more beneficial effects in antioxidant defense system of heart tissues than the use of crocin or voluntary exercise alone.

Temporary skin grafts based on hybrid graphene oxide-natural biopolymer nanofibers as effective wound healing substitutes: pre-clinical and pathological studies in animal models

In recent years, temporary skin grafts (TSG) based on natural biopolymers modified with carbon nanostructures have received considerable attention for wound healing. Developments are required to improve physico-mechanical properties of these materials to match to natural skins. Additionally, in-deep pre-clinical examinations are necessary to ensure biological performance and toxicity effect in vivo. In the present work, we show superior acute-wound healing effect of graphene oxide nanosheets embedded in ultrafine biopolymer fibers (60 nm) on adult male rats. Nano-fibrous chitosan-based skin grafts crosslinked by Genepin with physico-mechanical properties close to natural skins were prepared by electrospinning of highly concentrated chitosan- polyvinylpyrrolidone solutions containing graphene oxide (GO) nanosheets. No surfactants and organic solvents were utilized to ensure high biocompatibility of the fibrous structure. In vitro evaluations by human skin fibroblast cells including live and dead assay and MTT results show that GO promote cell viability of porous nanofibrous membrane while providing enhanced bactericidal capacity. In vivo studies on rat's skin determine accelerated healing effect, i.e. a large open wound (1.5 × 1.5 cm²) is fully regenerated after 14-day of post operation while healing is observed for sterile gauze sponge (as the control). Pathological studies support thick dermis formation and complete epithelialization in the presence of 1.5 wt% GO nanosheets. Over 99% wound healing occurs after 21 days for the injury covered with TSG containing 1.5 wt% GO while this would takes weeks for the control. Therefore, the developed materials have a high potential to be used as TSG as pre-clinical testing has shown.