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Lattice Radiation Therapy (LRT), a 3-dimentional format of Spatially Fractionated Radiation Therapy, is generally characterized by large differences in peak and valley doses. It has been shown in the literature that LTR administered before conventional external beam radiation treatment results in debulking effect, increased cell killing, and increased tumor growth delay. Traditionally, LRT is delivered by Linac-based radiation system. Particle-based LRT is in the experimental stages. LRT has never been applied to brain tumor. We present a new approach using Gamma Knife (GK) radiosurgery system to advance the application of lattice radiation therapy for tumors in brain. GK has superior localization accuracy, intrinsic spherical shape of the radiation shot, and sharp dose fall-off gradient, which are suitable to deliver LRT. Five cases of brain metastasis with large tumor volumes, previously treated with 2-stage GK SRS, were selected for LTR planning. The tumor volumes range from 14 to 31.8 mL. New Gamma Knife LRT (GKLRT) plans were generated in Leksell Gamma Plan v11.3. Based on the literature, 15Gy to the vertices was elected in this study, which is high enough to induce tumor immunogenic response. The valley dose of 5Gy between vertices were chosen as constraint during planning to preserve tumor perfusion integrity for circulation of immunogenic factors and increasing the therapeutic ratio. Vertices in the lattice were considered as targets in the plan. Multiple targets with single 4 mm shot were placed inside the GTV. The prescription for each target was 15Gy at 100%. These shots were placed manually in such pattern that every shot was at least 4 mm from GTV boundary, the spacing between shots in Z direction was 8 mm, and the spacing in X and Y direction was more than 12 mm. The goal of the manual planning was to place maximum number of shots, and maintain the 5Gy lines around each shot not connected and within GTV. Dose coverage for GTV was not in consideration during planning. In the new GKLRT plans, the point dose at each vertex was exactly 15Gy. The minimal valley dose between any two vertices was less than 5Gy. The maximum dose at GTV surface was less than 5Gy. On average, every 1.6 mL GTV can fit one vertex. Given dose rate of 2.5Gy/min, the treatment time for 30 vertices GKLRT plan is 221 minutes for instance. Dosimetric feasibility of using GKLRT to treat brain tumors is demonstrated. A phase I protocol is under development to introduce one fraction of GKLRT before routine brain SBRT for intact brain metastases. This new approach has promising potential to significantly improve the outcome of patients with bulky brain tumors. [ABSTRACT FROM AUTHOR]

Purpose: To provide a rapid method to reduce the radiofrequency (RF) E-field coupling and consequent heating in long conductors in an interventional MRI (iMRI) setup. Methods: A driving function for device heating (W) was defined as the integration of the E-field along the direction of the wire and calculated through a quasistatic approximation. Based on this function, the phases of four independently controlled transmit channels were dynamically changed in a 1.5 T MRI scanner. During the different excitation configurations, the RF induced heating in a nitinol wire immersed in a saline phantom was measured by fiber-optic temperature sensing. Additionally, a minimization of W as a function of phase and amplitude values of the different channels and constrained by the homogeneity of the RF excitation field (B1) over a region of interest was proposed and its results tested on the benchtop. To analyze the validity of the proposed method, using a model of the array and phantom setup tested in the scanner, RF fields and SAR maps were calculated through finite-difference time-domain (FDTD) simulations. In addition to phantom experiments, RF induced heating of an active guidewire inserted in a swine was also evaluated. Results: In the phantom experiment, heating at the tip of the device was reduced by 92% when replacing the body coil by an optimized parallel transmit excitation with same nominal flip angle. In the benchtop, up to 90% heating reduction was measured when implementing the constrained minimization algorithm with the additional degree of freedom given by independent amplitude control. The computation of the optimum phase and amplitude values was executed in just 12 s using a standard CPU. The results of the FDTD simulations showed similar trend of the local SAR at the tip of the wire and measured temperature as well as to a quadratic function of W, confirming the validity of the quasistatic approach for the presented problem at 64 MHz. Imaging and heating reduction of the guidewire were successfully performed in vivo with the proposed hardware and phase control. Conclusions: Phantom and in vivo data demonstrated that additional degrees of freedom in a parallel transmission system can be used to control RF induced heating in long conductors. A novel constrained optimization approach to reduce device heating was also presented that can be run in just few seconds and therefore could be added to an iMRI protocol to improve RF safety. [ABSTRACT FROM AUTHOR]

Focused impedance measurement (FIM) is a technique where impedance can be measured with the optimum level of localization without much increase in complexity of measuring instrument. The electrodes are applied on the skin surface while the organs inside also contribute to the measurement, as the body is a volume conductor. In a healthy and disease free lung region, the air enters at breathe-in, increases the impedance of the lung, and impedance reduces during breathe-out. In contrast, for a diseased lung, where part of the lungs is filled with water or some fluid, air will not enter into this zone reducing impedance change between inspiration and expiration. With this idea, the current work had been executed to have general view of localized impedance change throughout thorax using 6-electrode FIM. This generated a matrix mapping from both the front and from the back of the thorax, which showed how impedance change due to ventilation varies from frontal plane to back plane of human bodies.

Abstract Background Genomic RNA dimerization is an important process in the formation of an infectious lentiviral particle. One of the signals involved is the stem-loop 1 (SL1) element located in the leader region of lentiviral genomic RNAs which also plays a role in encapsidation and reverse transcription. Recent studies revealed that HIV types 1 and 2 leader RNAs adopt different conformations that influence the presentation of RNA signals such as SL1. To determine whether common mechanisms of SL1 regulation exist among divergent lentiviral leader RNAs, here we compare the dimerization properties of SIVmac239, HIV-1, and HIV-2 leader RNA fragments using homologous constructs and experimental conditions. Prior studies from several groups have employed a variety of constructs and experimental conditions. Results Although some idiosyncratic differences in the dimerization details were observed, we find unifying principles in the regulation strategies of the three viral RNAs through long- and short-range base pairing interactions. Presentation and efficacy of dimerization through SL1 depends strongly upon the formation or dissolution of the lower stem of SL1 called stem B. SL1 usage may also be down-regulated by long-range interactions involving sequences between SL1 and the first codons of the gag gene. Conclusion Despite their sequence differences, all three lentiviral RNAs tested in this study showed a local regulation of dimerization through the stabilization of SL1.

A typical workflow for complex cervical HDR brachytherapy planning at most institutions includes delineation of Organ at Risk (OAR) contours on a CT acquired after device placement. Additionally, at our institution, an MRI is obtained for HR CTV delineation. Then the plan is finalized and the treatment is delivered. Due to limited MRI slots, the completion of the MRI can take place up to six hours after the CT. This study aims to assess the potential deviations in OAR delineation and resulting dose statistics caused by variations in the time between CT and MRI scans. Data were acquired through an IRB-approved retrospective review of cervical cancer patients treated with HDR brachytherapy, utilizing both CT and MRI scans for treatment planning. OARs were delineated by our institution's radiation oncologists for 17 cases. Contours for rectum, bladder, bowel, and sigmoid were delineated on both CT and MRI. The MRI was fused to the CT based on the HR CTV and applicator and approved by the physician. The RT doses from the delivered clinical plans were overlaid to assess dose statistics for the two contour sets. Analysis was employed to determine differences in OAR doses between MRI and CT-based contours. The average time between CT and MRI scans was 4.34 ± 1.88 hrs (0.46-6.87 hrs). The mean ± STDev of D2cc for each OAR on CT and MRI, p value, and mean ± STDev of the percent difference of the two were determined for a single fraction. Rectum D2cc on CT and MRI was 3.40 ± 1.54 Gy and 3.64 ± 1.24 Gy respectively with p = 0.39 and average D2cc 34.5 ± 124% higher on MRI. This large STDev is attributed to 2 cases where the rectum moved significantly closer to the HR CTV. Without these 2 outliers, the average percent difference in D2cc was 0.68 ± 9.65%. Bladder D2cc on CT and MRI was 5.10 ± 1.35 Gy and 4.62 ± 1.37 Gy respectively with p = 0.02 and average D2cc 9.46 ± 16.3% lower on MRI. Sigmoid D2cc on CT and MRI was 2.68 ± 1.20 Gy and 2.70 ± 1.22 Gy respectively with p = 0.84 and average D2cc 3.17 ± 27.35% lower on MRI. D2cc for bowel was not evaluable for 6 cases (contours were outside of the 10x10cm dose grid). Bowel D2cc on CT and MRI was 3.63 ± 1.36 Gy and 2.90 ± 1.47 Gy respectively with p = 0.03 and average D2cc 20.2 ± 27.4% lower on MRI. The data show a significant decrease in D2cc to bladder and bowel when contoured on MRI as opposed to CT. There was no correlation between scan time difference and OAR D2cc percent difference between scans. The time difference between CT and MRI scans does not significantly impact dose to OAR contours in HDR brachytherapy treatment planning for cervical cancer. However, there was a small but significant decrease in D2cc to bowel and bladder when contoured on CT versus MRI independent of scan time difference. This may be due to improved delineation of these OARs on MRI. Contouring OARs on CT appears to have a conservative impact, implying it is safe to continue to contour OARs on the CT and the HR CTV on MRI. [ABSTRACT FROM AUTHOR]

Microporous annealed particle (MAP) hydrogels are a promising class of in situ-forming scaffolds for tissue repair and regeneration. While an expansive toolkit of annealing chemistries has been described, the effects of different annealing chemistries on MAP hydrogel properties and performance have not been studied. In this study, we address this gap through a controlled head-to-head comparison of poly(ethylene glycol) (PEG)-based MAP hydrogels that were annealed using tetrazine-norbornene and thiol-norbornene click chemistry. Characterization of material properties revealed that tetrazine click annealing significantly increases MAP hydrogel shear storage modulus and results in slower in vitro degradation kinetics when microgels with a higher cross-link density are used. However, these effects are muted when the MAP hydrogels are fabricated from microgels with a lower cross-link density. In contrast, in vivo testing in murine critical-sized calvarial defects revealed that these differences in physicochemical properties do not translate to differences in bone volume or calvarial defect healing when growth-factor-loaded MAP hydrogel scaffolds are implanted into mouse calvarial defects. Nonetheless, the impact of tetrazine click annealing could be important in other applications and should be investigated further.

To assess the knowledge and attitude of practicing physicians and surgeons towards the use of pain medication according to the World Health Organisation cancer pain analgesic ladder, the current study was conducted at tertiary care hospitals of the four provinces of Pakistan. Professionals having experience of treating cancer patients for >2 years were included. Data was collected using a self-administered questionnaire sent to each participant using Google Forms. Of the 630 physicians approached, 133(21%) responded. Of them, 74(55.64%) participants were familiar with the World Health Organisation analgesic ladder. There was a significant difference in the frequency of using the ladder based on age (p<0.05). Most participants 31(23%) reported the nonavailability of the recommended drugs as the reason for not following the analgesic ladder. There is a strong need to educate physicians and surgeons about the World Health Organisation analgesic ladder, and to make strategies to improve opioid availability in Pakistan.

While poly(ethylene glycol) (PEG) hydrogels are generally regarded as biologically inert blank slates, concerns over PEG immunogenicity are growing, and the implications for tissue engineering are unknown. Here, we investigate these implications by immunizing mice against PEG to stimulate anti-PEG antibody production and evaluating bone defect regeneration after treatment with bone morphogenetic protein-2-loaded PEG hydrogels. Quantitative analysis reveals that PEG sensitization increases bone formation compared to naive controls, whereas histological analysis shows that PEG sensitization induces an abnormally porous bone morphology at the defect site, particularly in males. Furthermore, immune cell recruitment is higher in PEG-sensitized mice administered the PEG-based treatment than their naive counterparts. Interestingly, naive controls that were administered a PEG-based treatment also develop anti-PEG antibodies. Sex differences in bone formation and immune cell recruitment are also apparent. Overall, these findings indicate that anti-PEG immune responses can impact tissue engineering efficacy and highlight the need for further investigation., (© 2024. The Author(s).)

To overcome the extensive heat generation inside the microprocessors nanofluids have gained importance because of their better thermophysical properties as compared with air and water. This work proposes a two-pronged strategy for thermal performance enhancement of mini channel heat sinks. Firstly, a novel dual flow slotted fin mini channel heat sink flow configuration is proposed. Secondly, a detailed numerical investigation is performed to assess heat transfer enhancement property of Al 2 O 3 -H 2 O and TiO 2 -H 2 O nanofluids. Considering the first step, fin spacing, number of slots, slot thickness and slot angle are investigated in detail yielding to the selection of best structural parameters. Two slots per fin of 0.5 mm thickness at an angle of 45° is selected because it provides better thermal performance as compared with water. Further, numerical assessment of nano fluid behavior was carried out at volumetric concentrations of 0.005% and 0.01%. For the case of novel dual flow slotted fin mini channel heat sink, maximum numerical and experimental advantages in all targeted system properties is observed for Al 2 O 3 -H 2 O nano fluid at volumetric concentration of 0.01%, as compared with water. Al 2 O 3 -H 2 O nano fluid provides better thermal performance both numerically and experimentally as compared with TiO 2 -H 2 O nanofluids. Increment in the pressure drop is noted with increasing volumetric concentrations., (© 2023 IOP Publishing Ltd.)

Complex regional pain syndrome (CRPS) is a chronic pain disorder characterized by pain that is disproportionate to the inciting event. Autonomic and inflammatory responses predominate, and treatment plans that explicitly target these responses reduce symptoms for longer periods of time, are typically better tolerated, and have more favorable outcomes. Our patient was a young male who presented with a four-month history of a road traffic accident (RTA) that resulted in a fractured left distal radius and scaphoid. His main complaint was pain and discomfort, even after surgical forearm stabilization, as well as hyperesthesia, restricted range of motion, and new-onset tremors. The patient was provisionally diagnosed with complex regional pain syndrome (CRPS) and booked for a fluoroscopically guided stellate ganglion block when the oral medication regime provided minimal relief. A stellate ganglion block was administered using a combination of ropivacaine, methylprednisolone, and dexmedetomidine under fluoroscopic guidance. During our routine outpatient follow-ups, our patient's pain score on the visual analog scale (VAS) fell to zero, the burning, vasomotor, and temperature abnormalities subsided, and he gradually regained the use of his left forearm and hand. The etiology of complex regional pain syndrome is multifaceted. Early identification and therapy typically halt the progression. Long-term outcomes are improved by treatment strategies that target inflammatory and autonomic responses. Dexmedetomidine has a mild anti-nociceptive action when used as an adjuvant in peripheral nerve blocks and ganglion blocks, blocking pain transmission in Aδ and C fibers. We feel that by combining dexmedetomidine and a stellate ganglion block, we could provide immediate and long-term relief to our patient. More research is needed to monitor and analyze the efficacy of dexmedetomidine as a treatment for chronic pain syndromes such as CRPS., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Sheikh et al.)

Background: Infectious disease outbreaks have always presented challenges to the operation of healthcare systems. In particular, the treatment of cancer patients within Radiation Oncology often cannot be delayed or compromised due to infection control measures. Therefore, there is a need for a strategic approach to simultaneously managing infection control and radiotherapy risks., Purpose: To develop a systematic risk management method that uses mathematical models to design mitigation efforts for control of an infectious disease outbreak, while ensuring safe delivery of radiotherapy., Methods: A two-stage failure mode and effect analysis (FMEA) approach is proposed to modify radiotherapy workflow during an infectious disease outbreak. In stage 1, an Infection Control FMEA (IC-FMEA) is conducted, where risks are evaluated based on environmental parameters, clinical interactions, and modeling of infection risk. occupancy risk index (ORI) is defined as a metric for infection transmission risk level in each room, based on the degree of occupancy. ORI, in combination with ventilation rate per person (R p ), is used to provide a broad infection risk assessment of workspaces. For detailed IC-FMEA of clinical processes, infection control failure mode (ICFM) is defined to be any instance of disease transmission within the clinic. Infection risk priority number (IRPN) has been formulated as a function of time, distance, and degree of protective measures. Infection control measures are then systematically integrated into the workflow. Since the workflow is perturbed by infection control measures, there is a possibility of introducing new radiotherapy failure modes or increased likelihood of existing failure modes. Therefore, in stage 2, a conventional radiotherapy FMEA (RT-FMEA) should be performed on the adjusted workflow., Results: The COVID-19 pandemic was used to illustrate stage 1 IC-FMEA. ORI and R p values were calculated for various workspaces within a clinic. A deep inspiration breath hold (DIBH) CT simulation was used as an example to demonstrate detailed IC-FMEA with ICFM identification and IRPN evaluation. A total of 90 ICFMs were identified in the DIBH simulation process. The calculated IRPN values were found to be progressively decreasing for workflows with minimal, moderate, and enhanced levels of protective measures., Conclusion: The framework developed in this work provides tools for radiotherapy clinics to systematically assess risk and adjust workflows during the evolving circumstances of any infectious disease outbreak., (© 2023 American Association of Physicists in Medicine.)

Background The duration and magnitude of increased stroke risk after a hospitalization for acute systolic heart failure (HF) remains uncertain. Methods and Results The authors performed a retrospective cohort study using claims (2008-2018) from a nationally representative 5% sample of Medicare beneficiaries aged ≥66 years. Cox regression models were fitted separately for the groups with and without acute systolic HF to examine its association with the incidence of ischemic stroke after adjustment for demographics, stroke risk factors, and Charlson comorbidities. Corresponding survival probabilities were used to compute the hazard ratio (HR) in each 30-day interval after discharge. The authors stratified patients by the presence of atrial fibrillation (AF) before or during the hospitalization for acute systolic HF. Among 2 077 501 eligible beneficiaries, 94 641 were hospitalized with acute systolic HF. After adjusting for demographics, stroke risk factors, and Charlson comorbidities, the risk of ischemic stroke was highest in the first 30 days after discharge from an acute systolic HF hospitalization for patients with AF (HR, 2.4 [95% CI, 2.1-2.7]) and without AF (HR, 4.6 [95% CI, 4.0-5.3]). The risk of stroke remained elevated for 60 days in patients with AF (HR, 1.4 [95% CI, 1.2-1.6]) and was not significantly elevated afterward. The risk of stroke remained significantly elevated through 330 days in patients without AF (HR, 2.1 [95% CI, 1.7-2.7]) and was no longer significantly elevated afterward. Conclusions A hospitalization for acute systolic HF is associated with an increased risk of ischemic stroke up to 330 days in patients without concomitant AF.

Freehand needles can be used with multichannel vaginal cylinders (MCVC) to cover vaginal cancer >7 mm thick or with supra-vaginal extension. We report our institutional outcomes using this novel hybrid technique. Patients with vaginal malignancies treated with HDR BT using MCVC plus freehand needles from 2014-2021 at our institution were identified. Clinical characteristics, details of brachytherapy, initial response, and overall local control (LC) outcomes were recorded. LC was analyzed via Kaplan-Meier method. 34 patients were identified with median follow-up 1.9 years. 19 patients had primary endometrial cancer with vaginal recurrence/disease, and remaining had primary vaginal cancer or other primaries. 7 patients had recurrence after previous RT course. 25 patients received EBRT with median dose 45 Gy in 25 fractions, and rest received BT alone. Median HR-CTV D90 for patients treated with EBRT plus BT was 77.4 Gy. 30 patients had complete local response to BT on initial examination and/or follow-up imaging. 1 and 2-year LC rates in patients without prior RT treated with EBRT + BT were 94.1% and 94.1%, respectively. 1 and 2-year LC rates for those without prior RT were 88.1% and 76.4%, respectively. 1 and 2-year LC rates for those with prior RT were 68.6% and 34.3%, respectively. 1 patient had vaginal laceration requiring surgical repair, and 1 patient developed small bowel obstruction 1 month after BT, with no additional acute grade 3+ toxicities identified. Our approach with MCVC plus freehand needles with MRI-based planning was feasible and safe, with excellent initial local response and low rate of serious toxicities., (Copyright © 2022 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Objective: To determine the prevalence of smoking and to evaluate the knowledge about preoperative smoking cessation in patients coming for elective surgery., Methods: The cross-sectional study was conducted from July 30, 2019, to March 17, 2020, in the preoperative anaesthesia assessment clinic and surgical wards of Aga Khan University Hospital, Civil Hospital Karachi, and Abbasi Shaheed Hospital, Karachi, and comprised all patients of either gender aged >12 years scheduled for elective surgery having American Society of Anaesthesiologists physical status I-IV. Data was analysed using Stata 13., Results: Of the 811 patients, 478(59%) were male and 333(41%) were female. The overall mean age was 43.4±16.4 years and mean BMI was 25.0±5.8kg/m2. There were 164(20.2%) smokers in the sample. The overall knowledge about preoperative smoking cessation was significantly associated with the level of education and gender (p<0.05)., Conclusions: Smoking in surgical patients was about one-fifth of the overall sample, and knowledge related to preoperative smoking abstinence was significantly associated with educational status and gender.

Objective: To identify service quality gaps by reviewing out-of-operating-room anaesthesia services in a tertiary care hospital., Methods: This quality improvement audit was conducted at The Aga Khan University Hospital Karachi from July to September 2019, and comprised procedures conducted outside the operating room under anaesthesia and sedation from 8am to 5pm. A data collection form was designed to collect information related to the non-operating-room anaesthesia services. Data was analysed using SPSS Version 19., Results: A total of 123 radiological procedures were observed in 48 working days and endoscopic/radio-therapeutic procedures observed were 98 over 31 days. The mean anaesthesia coverage time was 2.96±1.71 hours per day for radiological procedures, and 2.59±1.07 hours for endoscopic/radio-therapeutic procedures, indicating underutlisation of resources both human and material., Conclusions: A multideciplinary team consisting of all stakeholders should be developed to facilitate the patients and enhance healthcare quality.

Purpose: In this study, the effects of RF coupling on the magnitude and spatial patterns of RF-induced heating near multiple wire-like conducting implants (such as simultaneous electrical stimulation of stereoelectroencephalography electrodes) during MRI were assessed., Methods: Simulations and experimental measurements of RF-induced temperature increases near partially immersed wire-like conductors were performed using a phantom with a transmit/receive head coil on a 3T MRI system. The conductors consisted of either a pair of wires or a single simultaneous electrical stimulation of stereoelectroencephalography electrode with multiple contacts, and the locations and lengths of the conductors were varied to study the effect of electromagnetic coupling on RF-induced heating., Results: The temperature increase near a wire within the phantom was dependent not only on its own location and length, but also on the locations and lengths of the other partially immersed wires. In the configurations that were studied, the presence of a second implant could increase the heating near the tip of the conductor by as much as 95%., Conclusion: The level of RF-induced heating during an MR scan is affected significantly by RF coupling when more than one wire-like implant is present. In some of the configurations studied, the heating was increased by the presence of a second conductor partially immersed in the phantom. Thus, RF coupling is an important factor to consider in the assessment of safety issues for MRI when multiple implants are present., (© 2022 International Society for Magnetic Resonance in Medicine.)

Background: Obesity is a growing public health concern and is one of the leading causes of human suffering and disability worldwide. The number of overweight and obese people is dramatically increasing, and local data showed that low back pain (LBP) is more common in people with obesity, prolonged sitting jobs, psychological disorders, and lack of exercise., Methods: This study was conducted in a cohort of 300 adult patients of either gender who visited a pain management clinic with LBP. Patient data were retrieved from the hospital software program and recorded in a pre-designed proforma. The data included the patient's age, gender, weight, height, BMI, comorbidities, site of pain, duration of pain, distribution of pain, severity of pain, history of spinal trauma, previous spinal surgery, and working diagnosis., Results: Out of 300 patients with LBP, 185 (61.7 %) were female and 115 (38.3%) were male, of these, 224 (74.6%) were overweight or obese. One hundred and three (34.3%) had axial back pain and 197 (65.7%) patients had lumbar radicular pain. Linear regression analysis showed that 17% variability in pain scores in both genders can be explained by the increase in BMI. There is a statistically significant relationship, i.e. P=0.0005, exists between pain score and BMI., Conclusion: This study showed the strong association between obesity and LBP in the Pakistani population. Approximately, 75% were overweight or obese in our LBP population-based cohort and this association was stronger among women than men., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2022, Siddiqui et al.)

Background and Purpose: Ureteral stenosis (US) is an underreported complication of brachytherapy (BT) for cervical cancer (CC), with limited data on toxicity risk reduction. A previous study demonstrated ureter EQD2 D0.1cc > 77 Gy correlated with US development. We sought to assess feasibility of this constraint while maintaining similar HR-CTV coverage., Materials and Methods: Patients with locally advanced CC treated with EBRT plus HDR MRI-based brachytherapy boost without hydronephrosis at diagnosis and with ureter dose EQD2 D0.1cc > 77 Gy were included. Replan was attempted to achieve HR-CTV D90 ≥ 80-85 Gy and ureter dose reduction. Ureter distance from lateral margin of HR-CTV and tandem was recorded. t-test was performed to compare ureteral dose and HR-CTV D90., Results: Of 25 patients were identified. Hundred percent received 45 Gy in 25 fractions to the pelvis ± paraaortic lymph nodes and 80% receiving median additional parametrial dose of 5.4 Gy. Replan meeting ureteral dose of ≤77 Gy was feasible in 18 of 25 patients, with a reduction in median ureter D0.1cc from 82.3 to 76.8 Gy (p < 0.001). Median HR-CTV D90 was similar (84.7 vs. 85.0 Gy). Replan achieved D0.1cc ≤77 Gy in 56% of patients who experienced US. All unilateral US cases occurred in the ureter closest to HR-CTV., Conclusions: Optimization to reduce ureter dose to ≤77 Gy is feasible when ureters are visible and contoured. Ureters may be considered as potential OAR during MRI-based brachytherapy treatment. Reduced ring to tandem total reference air kerma (TRAK) ratio may provide an additional metric by which to lower US risk., (Copyright © 2021 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Background: The parent-adolescent relationship plays a key role in adolescent development, including behaviour, physical health, and mental health outcomes. Studies on the parental factors that contribute to an adolescent's dietary habits, exercise, mental health, physical harm and substance use are limited in the Middle East and North Africa region, with none in Oman. This study aims to investigate the association between parental involvement and adolescent well-being in Oman., Methods: Cross-sectional data from the 2015 Global School Health Survey for Oman was analysed. The dataset consisted of 3468 adolescents. Adolescents reported on their parental involvement (checking to see if they did their homework, understanding their problems, knowing what they are doing in their free time and not going through their things without permission). Parental involvement was scored on a 20-point scale. Associations with the following dependent variables: nutrition, exercise, hygiene, physical harm, bullying, substance use, tobacco use and mental health well-being were done using Spearman's correlations, linear and logistic regressions., Results: The surveyed population was 48% male, 65% aged 15 to 17 years old and 5% reported that they "most of the time or always" went hungry. Parental involvement was positively correlated with each of the dependent variables. Adolescents with higher parental involvement had significantly higher odds of good nutrition (1.391), hygiene (1.823) and exercise (1.531) and lower odds of physical harm (0.648), being bullied (0.628), poor mental health (0.415), tobacco use (0.496) and substance use (0.229)., Conclusions: Parental involvement plays a positive role in all aspects of adolescents' well-being in Oman. Awareness campaigns and interventions aimed to help improve the well-being of adolescents should incorporate such positive role in their designs., (© 2021. The Author(s).)

Objective: Pivotal clinical trials revealed good clinical efficiency of ocrelizumab while having a good safety profile in the management of multiple sclerosis (MS). However, real-world data of ocrelizumab in daily clinical practice remain scarce. The aim of this study was to evaluate the preliminary safety profile and effectiveness of ocrelizumab treatment for MS in an Arab population in a real-world clinical setting., Methods: In this retrospective single-center observational study in Qatar, we reviewed the medical records and analyzed the clinical and MRI data of all patients with relapsing-remitting MS (RRMS) and active secondary progressive MS (aSPMS)-between October 2017 through December 2020-who had received at least one infusion of ocrelizumab (Q-OCRE)., Results: A total of 60 MS patients were included (57 with RRMS, three SPMS). The Median follow-up period was 19 months (range, 1-32). The most common reason for switching to ocrelizumab was increased disease activity and three-quarters of the patients were on a previous disease-modifying drug (DMD). No evidence of disease activity (NEDA) status at year 1 was achieved in 73% of the cohort. Mild infusion-related reactions (IRR) and infections were reported (mainly upper respiratory tract infections followed by urinary tract infection) with a declining percentage over the follow-up applications. No severe side effects were observed., Conclusion: Our real-world experience confirms good efficacy, tolerability, and safety of ocrelizumab in our Arab population., (© 2021 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)