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1.
Mol Biol Rep ; 51(1): 791, 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38990430

ABSTRACT

BACKGROUND: Heat stress is a detrimental abiotic stress that limits the development of many plant species and is linked to a variety of cellular and physiological problems. Heat stress affects membrane fluidity, which leads to negative effects on cell permeability and ion transport. Research reveals that heat stress causes severe damage to cells and leads to rapid accumulation of reactive oxygen species (ROS), which could cause programmed cell death. METHODS AND RESULTS: This current study aimed to validate the role of Triticum aestivum Salt Stress Root Protein (TaSSRP) in plants' tolerance to heat stress by modulating its expression in tobacco plants. The Relative Water Content (RWC), total chlorophyll content, and Membrane Stability Index (MSI) of the seven distinct transgenic lines (T0 - 2, T0 - 3, T0 - 6, T0 - 8, T0 - 9, T0 - 11, and T0 - 13), increased in response to heat stress. Despite the fact that the same tendency was detected in wild-type (WT) plants, changes in physio-biochemical parameters were greater in transgenic lines than in WT plants. The expression analysis revealed that the transgene TaSSRP expressed from 1.00 to 1.809 folds in different lines in the transgenic tobacco plants. The gene TaSSRP offered resistance to heat stress in Nicotiana tabacum, according to the results of the study. CONCLUSION: These findings could help to improve our knowledge and understanding of the mechanism underlying thermotolerance in wheat, and the novel identified gene TaSSRP could be used in generating wheat varieties with enhanced tolerance to heat stress.


Subject(s)
Gene Expression Regulation, Plant , Heat-Shock Response , Nicotiana , Plant Proteins , Plants, Genetically Modified , Triticum , Nicotiana/genetics , Nicotiana/metabolism , Triticum/genetics , Triticum/metabolism , Plants, Genetically Modified/genetics , Plant Proteins/genetics , Plant Proteins/metabolism , Heat-Shock Response/genetics , Reactive Oxygen Species/metabolism , Plant Roots/metabolism , Plant Roots/genetics , Thermotolerance/genetics , Chlorophyll/metabolism , Salt Tolerance/genetics
2.
Sci Rep ; 13(1): 5795, 2023 04 09.
Article in English | MEDLINE | ID: mdl-37032381

ABSTRACT

Natural regeneration of degraded reefs relies on the recruitment of larvae to restore populations. Intervention strategies are being developed to enhance this process through aquaculture production of coral larvae and their deployment as spat. Larval settlement relies on cues associated with crustose coralline algae (CCA) that are known to induce attachment and metamorphosis. To understand processes underpinning recruitment, we tested larval settlement responses of 15 coral species, to 15 species of CCA from the Great Barrier Reef (GBR). CCA in the family Lithophyllaceae were overall the best inducer across most coral species, with Titanoderma cf. tessellatum being the most effective species that induced at least 50% settlement in 14 of the coral species (mean 81%). Taxonomic level associations were found, with species of Porolithon inducing high settlement in the genus Acropora; while a previously understudied CCA, Sporolithon sp., was a strong inducer for the Lobophyllidae. Habitat-specific associations were detected, with CCA collected from similar light environment as the coral inducing higher levels of settlement. This study revealed the intimate relationships between coral larvae and CCA and provides optimal coral-algal species pairings that could be utilized to increase the success of larval settlement to generate healthy spat for reef restoration.


Subject(s)
Anthozoa , Rhodophyta , Animals , Anthozoa/physiology , Larva/physiology , Ecosystem , Cues , Coral Reefs
3.
Front Oncol ; 11: 620978, 2021.
Article in English | MEDLINE | ID: mdl-33816253

ABSTRACT

PURPOSE: Enhance rectum and bladder sparing in prostate SBRT with minimum increase in treatment time by complementing dual-arc coplanar VMAT with a two-beam non-coplanar IMRT class solution (CS). METHODS: For twenty patients, an optimizer for automated multi-criterial planning with integrated beam angle optimization (BAO) was used to generate dual-arc VMAT plans, supplemented with five non-coplanar IMRT beams with individually optimized orientations (VMAT+5). In all plan generations, reduction of high rectum dose had the highest priority after obtaining adequate PTV coverage. A CS with two most preferred directions in VMAT+5 and largest rectum dose reductions compared to dual-arc VMAT was then selected to define VMAT+CS. VMAT+CS was compared with automatically generated i) dual-arc coplanar VMAT plans (VMAT), ii) VMAT+5 plans, and iii) IMRT plans with 30 patient-specific non-coplanar beam orientations (30-NCP). Plans were generated for a 4 x 9.5 Gy fractionation scheme. Differences in PTV doses, healthy tissue sparing, and computation and treatment delivery times were quantified. RESULTS: For equal PTV coverage, VMAT+CS, consisting of dual-arc VMAT supplemented with two fixed, non-coplanar IMRT beams with fixed Gantry/Couch angles of 65°/30° and 295°/-30°, significantly reduced OAR doses and the dose bath, compared to dual-arc VMAT. Mean relative differences in rectum Dmean, D1cc, V40GyEq and V60GyEq were 19.4 ± 10.6%, 4.2 ± 2.7%, 34.9 ± 20.3%, and 39.7 ± 23.2%, respectively (all p<0.001). There was no difference in bladder D1cc, while bladder Dmean reduced by 17.9 ± 11.0% (p<0.001). Also, the clinically evaluated urethra D5%, D10%, and D50% showed small, but statistically significant improvements. All patient VX with X = 2, 5, 10, 20, and 30 Gy were reduced with VMAT+CS, with a maximum relative reduction for V10Gy of 19.0 ± 7.3% (p<0.001). Total delivery times with VMAT+CS only increased by 1.9 ± 0.7 min compared to VMAT (9.1 ± 0.7 min). The dosimetric quality of VMAT+CS plans was equivalent to VMAT+5, while optimization times were reduced by a factor of 25 due to avoidance of individualized BAO. Compared to VMAT+CS, the 30-NCP plans were only favorable in terms of dose bath, at the cost of much enhanced optimization and delivery times. CONCLUSIONS: The proposed two-beam non-coplanar class solution to complement coplanar dual-arc VMAT resulted in substantial plan quality improvements for OARs (especially rectum) and reduced irradiated patient volumes with minor increases in treatment delivery times.

4.
Transplant Proc ; 53(3): 856-864, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33487455

ABSTRACT

Malaysia has a low deceased-donor donation rate and has not embarked on a paired kidney exchange program; therefore, ABO-incompatible and HLA-incompatible transplantation remain the main contributor to the sustainability of the national kidney transplantation (KT) program. There were 26 cases of ABO-incompatible KTs performed from 2011 to 2018 in 3 major transplant centers, namely, Hospital Kuala Lumpur, University Malaya Medical Centre, and Prince Court Medical Centre. We collected perioperative and follow-up data through June 2019. The desensitization protocol varies and is center specific: the localized Japanese protocol and Swedish protocol with a target anti-A/B isoagglutinin titer of 16 or 32 on the day of transplant. The induction and tacrolimus-based maintenance protocol was nearly identical. The median follow-up time was 62.3 months (interquartile range, 37.0-79.7). Fifteen subjects had the highest predesensitization anti-A/B titer of ≥32 (57.7%). The acute cellular rejection and antibody-mediated rejection incidence were 12.5% (3 cases) and 8.3% (2 cases), respectively. Patient, graft, and death-censored graft survival rates were 96.2%, 92.3%, and 96.0%, respectively, 1 year post-living-donor KT (LDKT) and 96.2%, 87.2%, and 90.7%, respectively, 5 years post-LDKT. Our experience shows that ABO-incompatible LDKT using a suitable desensitization technique could be a safe and feasible choice for LDKT even with varied desensitization regimens for recipients with relatively high baseline isoagglutinin titers.


Subject(s)
Blood Group Incompatibility/mortality , Desensitization, Immunologic/mortality , Graft Rejection/mortality , Graft Survival/immunology , Kidney Transplantation/mortality , Adult , Antibodies/immunology , Blood Group Incompatibility/immunology , Desensitization, Immunologic/methods , Developing Countries , Feasibility Studies , Female , Graft Rejection/immunology , Humans , Kidney/immunology , Kidney Transplantation/methods , Living Donors , Malaysia , Male , Middle Aged , Survival Rate , Treatment Outcome
5.
Anemia ; 2020: 7080264, 2020.
Article in English | MEDLINE | ID: mdl-32908695

ABSTRACT

BACKGROUND: Blood transfusion is an essential component in the care of patients with sickle cell disease (SCD), but it might be associated with serious acute and delayed complications. This study was aimed to describe red cell transfusion patterns and indications among hospitalized SCD children in a low-resource setting. Patients and Methods. A retrospective, descriptive study of all children (≤16 years) with SCD who received blood transfusion therapy during their hospital admissions in the pediatric department at Al-Sadaqa Teaching Hospital in Aden, Yemen, for a period of one year. RESULTS: Out of 217 hospitalized children with SCD, 169 (77.9%) were transfused and received 275 RBC transfusion episodes. The mean age of transfused children was 6.9 ± 4.6 years and 103 (60.9%) were males, with a male/female ratio of 1.6 : 1 (p=0.004). Hemoglobin (Hb) levels were significantly lower in the transfused than in the nontransfused (Hb 5.5 ± 1.5 vs. 7.7 ± 1.5 g/dL, p=0.03). Pretransfusion Hb levels were ˂7.0 g/dL in 86.2% and ˂5.0 g/dL in 39.3% of patients. Single transfusion was given to 122 (72.2%) and 5 or more transfusions in 9 (4.15%) of patients on different occasions. Simple (top-up) transfusion was used in all transfusion events. Commonest indications for transfusion were anemic crises (41.1%), vasoocclusive crises (VOC) (13.8%), VOC with anemic event (11.3%), acute chest syndrome (8.7%), and stroke (7.3%). CONCLUSION: Intermittent blood transfusion remains a common practice for the management of children with acute SCD complications. Main indications were acute anemic crises, severe pain crises, ACS, and stroke. In limited resource settings, such as Yemen, conservative transfusion policy appears to be appropriate.

6.
Radiother Oncol ; 142: 147-153, 2020 01.
Article in English | MEDLINE | ID: mdl-31522879

ABSTRACT

BACKGROUND AND PURPOSE: Radiotherapy of skull-base meningiomas is challenging due to the close proximity of multiple sensitive organs at risk (OARs). This study systematically compared intensity modulated proton therapy (IMPT), non-coplanar volumetric modulated arc therapy (VMAT) and intensity modulated radiotherapy (IMRT) based on automated treatment planning. Differences in OARs sparing, with specific focus on the hippocampi, and low-dose delivery were quantified. MATERIALS AND METHODS: Twenty patients, target diameter >3 cm, were included. Automated plan generation was used to calculate a VMAT plan with three non-coplanar arcs, an IMRT plan with nine non-coplanar beams with optimized gantry and couch angles, and an IMPT plan with three patient-specific selected non-coplanar beams. A prescription dose of 50.4 GyRBE in 28 fractions was used. The same set of constraints and prioritized objectives was used. All plans were rescaled to the same target coverage. Repeated measures ANOVA was used to assess the statistical significance of differences in OAR dose parameters between planning techniques. RESULTS: Compared to VMAT and IMRT, IMPT significantly improved dose conformity to the target volume. Consequently, large dose reductions in OARs were observed. With respect to VMAT, the mean dose and D40% in the bilateral hippocampus were on average reduced by 48% and 74%, respectively (p ≤ 0.005). With IMPT, the mean dose in the normal brain and volumes receiving 20-30 Gy were up to 47% lower (p ≤ 0.01). When comparing IMPT and IMRT, even larger dose differences in those OARs were observed. CONCLUSION: For skull-base meningiomas IMPT allows for a considerable dose reduction in the hippocampi, normal brain and other OARs compared to both non-coplanar VMAT and IMRT, which may lead to a clinically relevant reduction of late neurocognitive side effects.


Subject(s)
Hippocampus/radiation effects , Meningeal Neoplasms/radiotherapy , Meningioma/radiotherapy , Photons/therapeutic use , Proton Therapy/methods , Skull Base Neoplasms/radiotherapy , Brain/diagnostic imaging , Brain/radiation effects , Hippocampus/diagnostic imaging , Humans , Meningeal Neoplasms/diagnostic imaging , Meningioma/diagnostic imaging , Organs at Risk/radiation effects , Radiotherapy Dosage , Radiotherapy Planning, Computer-Assisted/methods , Radiotherapy, Intensity-Modulated/methods , Skull Base Neoplasms/diagnostic imaging
7.
Saudi J Kidney Dis Transpl ; 30(4): 832-842, 2019.
Article in English | MEDLINE | ID: mdl-31464240

ABSTRACT

Microalbuminuria (MA) has been recognized as a sensitive marker of early glomerular injury and a predictor of kidney dysfunction in patients with sickle cell disease (SCD). Limited data are available about MA in SCD children in the Arab countries and none from Yemen. The aim of this study is to determine the prevalence and correlates of MA among 101 children aged 1-16 years, with SCD at their steady state. Children were recruited during their routine health-care visits to the pediatric outpatient clinic in Al-Sadaqa general teaching hospital, Aden, Yemen, between September 2014 and February 2015. A random spot urine sample for each child was screened for MA using Micral-Test strips method. Data on clinical history, anthropometry, blood pressure (BP), and laboratory investigations were obtained. The overall prevalence of MA in this sample was 30.7%, with male predominance (80.6%) (P <0.05). The mean age of children with MA was 7.5 ± 3.2 years, and 10% of them were under five years of age. MA was correlated to both hemoglobin and hematocrit levels, which found to have protective effect against MA (Odds ratio = 0.17 and 0.59, respectively, P <0.05). No correlations were found between MA with age, height, weight, body mass index, recurrent clinical events (painful crises, blood transfusions, and hospitalizations), or fetal hemoglobin levels. BP measurements for all individuals were within the normal ranges, but systolic and diastolic BP were significantly higher in those with MA than without. This study demonstrated a high prevalence of MA in Yemeni children with SCD, and affecting young children as early as 2.5 years of age. Screening for MA as one of the early renal injury markers in children with SCD may help in the prevention of permanent loss of renal function and subsequent renal insufficiency in adulthood.


Subject(s)
Albuminuria/epidemiology , Anemia, Sickle Cell/epidemiology , Kidney Diseases/epidemiology , Adolescent , Age Factors , Albuminuria/diagnosis , Albuminuria/urine , Anemia, Sickle Cell/blood , Anemia, Sickle Cell/diagnosis , Child , Child, Preschool , Cross-Sectional Studies , Female , Humans , Infant , Kidney Diseases/diagnosis , Kidney Diseases/urine , Male , Prevalence , Risk Factors , Sex Factors , Yemen/epidemiology
8.
Breast ; 46: 136-143, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31176055

ABSTRACT

INTRODUCTION: Breast-conserving surgery (BCS) with radiation therapy is the procedure of choice for early-stage breast cancer. Survival and locoregional recurrence is non-inferior to mastectomy, with superior cosmetic and psycho-social outcomes. Differing health systems have demonstrated a wide variation in the rate of BCS. Little is known about the rate of BCS and factors influencing its practice in middle resource countries. This study aims to examine the BCS rates in Malaysia and to identify factors influencing its uptake. METHODOLOGY: This is a multi-centre, cross-sectional study involving the University of Malaya Medical Centre (UMMC), Queen Elizabeth II Hospital (QEH), and Tengku Ampuan Rahimah Hospital (TARH). Patients diagnosed with invasive breast cancer from January 2014 to December 2015 were included, excluding stromal cancers and lymphomas. Univariate and multivariate analyses identified factors influencing BCS. RESULTS: A total of 1005 patients were diagnosed with breast cancer in the allocated time frame. Excluding incomplete records and those who did not have surgery, 730 patients were analysed. Overall BCS rate was 32.9%. The BCS rate was highest at QEH (54.1%), followed by UMMC (29.5%), and TARH (17.4%). 16.9% had BCS after neoadjuvant therapy. Factors influencing BCS uptake included age, ethnic group, breast-surgeon led services, AJCC Stage, tumour size, HER-2 expression, and tumour grade. CONCLUSIONS: The rate of BCS in Malaysia is low. A wide variation of rate exists among the studied hospitals. Younger age, earlier AJCC stage, and the presence of a Breast sub-specialist surgeon, would make it more likely that the patient has her breast conserved.


Subject(s)
Breast Neoplasms/surgery , Ethnicity/statistics & numerical data , Hospitals, Public/statistics & numerical data , Mastectomy, Segmental/statistics & numerical data , Adult , Aged , Breast Neoplasms/ethnology , Breast Neoplasms/pathology , Cross-Sectional Studies , Female , Health Services Accessibility/statistics & numerical data , Humans , Malaysia , Middle Aged , Multivariate Analysis , Neoplasm Staging
9.
East Mediterr Health J ; 24(12): 1119-1126, 2019 Feb 18.
Article in English | MEDLINE | ID: mdl-30799551

ABSTRACT

BACKGROUND: Impaired nutritional status is a major health problem affecting young children in developing countries that has a significant impact on child morbidity and mortality. AIMS: This study aimed to assess the prevalence of undernutrition among children aged < 5 years, using conventional indices and the Composite Index of Anthropometric Failure (CIAF), and then comparing their estimated results. METHODS: A community-based cross-sectional study was conducted and information was collected through house-tohouse visits using precoded structured records. We analysed data from 1292 children aged 6-59 months, from Ahwar and Al-Mahfed rural districts in Abyan Governate, South Yemen, with reference to the 2006 World Health Organization growth standards. RESULTS: CIAF identified undernutrition in 70.1% of children, while conventional anthropometric indices revealed 38.5% stunting, 39.9% wasting, and 55.1% underweight. Compared with conventional indices, CIAF aggregate recognized 31.6%, 30.2% and 15% more undernourished children than stunting, wasting and underweight separately. According to CIAF, 21% had a single anthropometric failure and 49.2% exhibited multiple failures. Stunting Index, Wasting Index and Underweight Index were 0.55, 0.57 and 0.79, respectively. CONCLUSIONS: CIAF gives a better estimate of undernutrition than currently used conventional indices; identifies more children with multiple anthropometric failures; and reflects a wider view of the extent and pattern of undernutrition of children living in communities with limited resource settings.


Subject(s)
Anthropometry/methods , Child Nutrition Disorders/diagnosis , Nutrition Assessment , Child Nutrition Disorders/epidemiology , Child, Preschool , Cross-Sectional Studies , Female , Humans , Infant , Male , Prevalence , Rural Population , Yemen/epidemiology
10.
East. Mediterr. health j ; 24(12): 1119-1126, 2018-12.
Article in English | WHO IRIS | ID: who-361501

ABSTRACT

Background: Impaired nutritional status is a major health problem affecting young children in developing countries that has a significant impact on child morbidity and mortality.Aims: This study aimed to assess the prevalence of undernutrition among children aged < 5 years, using conventional indices and the Composite Index of Anthropometric Failure (CIAF), and then comparing their estimated results.Methods: A community-based cross-sectional study was conducted and information was collected through house-to-house visits using precoded structured records. We analysed data from 1292 children aged 6–59 months, from Ahwar and Al-Mahfed rural districts in Abyan Governate, South Yemen, with reference to the 2006 World Health Organization growth standards. Results: CIAF identified undernutrition in 70.1% of children, while conventional anthropometric indices revealed 38.5% stunting, 39.9% wasting, and 55.1% underweight. Compared with conventional indices, CIAF aggregate recognized 31.6%, 30.2% and 15% more undernourished children than stunting, wasting and underweight separately. According to CIAF, 21% had a single anthropometric failure and 49.2% exhibited multiple failures. Stunting Index, Wasting Index and Under-weight Index were 0.55, 0.57 and 0.79, respectively. Conclusions: CIAF gives a better estimate of undernutrition than currently used conventional indices; identifies more children with multiple anthropometric failures; and reflects a wider view of the extent and pattern of undernutrition of children living in communities with limited resource settings.


Contexte : L’altération de l’état nutritionnel est un grave problème de santé qui touche les jeunes enfants dans les pays à faible revenu et qui a un impact significatif sur la morbidité et la mortalité infantiles.Objectifs : La présente étude visait à évaluer la prévalence de la dénutrition chez les enfants de moins de 5 ans en utilisant les indices classiques et l’indice composite d’insuffisance anthropométrique, puis en comparant leurs résultats estimés. Méthodes : Une étude communautaire transversale a été réalisée et des informations ont été recueillies au moyen d’un document structuré précodé lors de visites porte-à-porte. Nous avons analysé les données relatives à 1292 enfants âgés entre 6 et 59 mois des districts ruraux d’Ahwar et d’Al-Mahfed, dans le gouvernorat d’Abyan (sud du Yémen), par rapport aux normes de croissance publiées en 2006 par l’OMS. Résultats : D’après l’indice composite d’insuffisance anthropométrique, 70 % des enfants souffraient de dénutrition. Selon les indices anthropométriques classiques, les prévalences du retard de croissance, de l’émaciation et du déficit pondéral étaient de 38,5 %, 39,9 % et 55,1 % respectivement. L’indice composite susmentionné, qui fournit un chiffre agrégé, a ainsi identifié 31,5 %, 30,1 % et 14,9 % d’enfants dénutris en plus que les mesures du retard de croissance, de l’émaciation et du déficit pondéral prises séparément. D’après cet indice composite, 21 % des enfants présentaient une seule insuffisance anthropométrique et 49,2 % présentaient des insuffisances multiples. Les indices de retard de croissance, d’émaciation et de déficit pondéral obtenus étaient, respectivement, de 0,55, 0,57 et 0,79. Conclusions : L’indice composite d’insuffisance anthropométrique donne un meilleur aperçu de la dénutrition que les indices classiques actuellement utilisés. Il identifie en outre plus d’enfants souffrant d’insuffisances anthropométriques multiples et brosse un tableau plus complet de l’ampleur et de la nature du problème de la dénutrition des enfants vivant dans des communautés où les ressources sont limitées.


Subject(s)
Nutritional Sciences , Malnutrition , Prevalence , Child , Patient Outcome Assessment , Anthropometry , Cross-Sectional Studies , Rural Population , Yemen , Mediterranean Region
11.
Genome Biol Evol ; 10(8): 2102-2109, 2018 08 01.
Article in English | MEDLINE | ID: mdl-30060167

ABSTRACT

Neisseria meningitidis is the leading cause of epidemic meningitis in the "meningitis belt" of Africa, where clonal waves of colonization and disease are observed. Point mutations and horizontal gene exchange lead to constant diversification of meningococcal populations during clonal spread. Maintaining a high genomic diversity may be an evolutionary strategy of meningococci that increases chances of fixing occasionally new highly successful "fit genotypes". We have performed a longitudinal study of meningococcal carriage and disease in northern Ghana by analyzing cerebrospinal fluid samples from all suspected meningitis cases and monitoring carriage of meningococci by twice yearly colonization surveys. In the framework of this study, we observed complete replacement of an A: sequence types (ST)-2859 clone by a W: ST-2881 clone. However, after a gap of 1 year, A: ST-2859 meningococci re-emerged both as colonizer and meningitis causing agent. Our whole genome sequencing analyses compared the A population isolated prior to the W colonization and disease wave with the re-emerging A meningococci. This analysis revealed expansion of one clone differing in only one nonsynonymous SNP from several isolates already present in the original A: ST-2859 population. The colonization bottleneck caused by the competing W meningococci thus resulted in a profound reduction in genomic diversity of the A meningococcal population.


Subject(s)
Neisseria meningitidis/genetics , Genetic Variation , Ghana , Humans , Meningitis/cerebrospinal fluid , Meningitis/microbiology , Neisseria meningitidis/isolation & purification , Phylogeny , Recombination, Genetic
12.
Radiother Oncol ; 128(2): 349-356, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29885745

ABSTRACT

PURPOSE/OBJECTIVE: Assess to what extent the use of automated treatment planning would have reduced organ-at-risk dose delivery observed in the randomized HYPRO trial for prostate cancer, and estimate related toxicity reductions. Investigate to what extent improved plan quality for hypofractionation scheme as achieved with automated planning can potentially reduce observed enhanced toxicity for the investigated hypofractionation scheme to levels observed for conventional fractionation scheme. MATERIAL/METHODS: For 725 trial patients, VMAT plans were generated with an algorithm for automated multi-criterial plan generation (autoVMAT). All clinically delivered plans (CLINICAL), generated with commonly applied interactive trial-and-error planning were also available for the investigations. Analyses were based on dose-volume histograms (DVH) and predicted normal tissue complication probabilities (NTCP) for late gastrointestinal (GI) toxicity. RESULTS: Compared to CLINICAL, autoVMAT plans had similar or higher PTV coverage, while large and statistically significant OAR sparing was achieved. Mean doses in the rectum, anus and bladder were reduced by 7.8 ±â€¯4.7 Gy, 7.9 ±â€¯6.0 Gy and 4.2 ±â€¯2.9 Gy, respectively (p < 0.001). NTCPs for late grade ≥2 GI toxicity, rectal bleeding and stool incontinence were reduced from 23.3 ±â€¯9.1% to 19.7 ±â€¯8.9%, from 9.7 ±â€¯2.8% to 8.2 ±â€¯2.8%, and from 16.8 ±â€¯8.5% to 13.1 ±â€¯7.2%, respectively (p < 0.001). Reductions in rectal bleeding NTCP were observed for all published Equivalent Uniform Dose volume parameters, n. AutoVMAT allowed hypofractionation with predicted toxicity similar to conventional fractionation with CLINICAL plans. CONCLUSION: Compared to CLINICAL, autoVMAT had superior plan quality, with meaningful NTCP reductions for both conventional fractionation and hypofractionation schemes. AutoVMAT plans might reduce toxicity for hypofractionation to levels that were clinically observed (and accepted) for conventional fractionation. This may be relevant when considering clinical use of the investigated hypofractionation schedule with relatively high fraction dose (3.4 Gy).


Subject(s)
Prostatic Neoplasms/radiotherapy , Radiotherapy, Intensity-Modulated/adverse effects , Aged , Algorithms , Dose Fractionation, Radiation , Humans , Male , Middle Aged , Probability , Radiation Dose Hypofractionation , Radiotherapy Dosage , Radiotherapy Planning, Computer-Assisted/methods , Rectum/radiation effects , Urinary Bladder/radiation effects
13.
Radiat Oncol ; 13(1): 74, 2018 Apr 23.
Article in English | MEDLINE | ID: mdl-29685166

ABSTRACT

BACKGROUND: Postoperative/adjuvant radiotherapy of advanced gastric cancer involves a large planning target volume (PTV) with multi-concave shapes which presents a challenge for volumetric modulated arc therapy (VMAT) planning. This study investigates the advantages of automated VMAT planning for this site compared to manual VMAT planning by expert planners. METHODS: For 20 gastric cancer patients in the postoperative/adjuvant setting, dual-arc VMAT plans were generated using fully automated multi-criterial treatment planning (autoVMAT), and compared to manually generated VMAT plans (manVMAT). Both automated and manual plans were created to deliver a median dose of 45 Gy to the PTV using identical planning and segmentation parameters. Plans were evaluated by two expert radiation oncologists for clinical acceptability. AutoVMAT and manVMAT plans were also compared based on dose-volume histogram (DVH) and predicted normal tissue complication probability (NTCP) analysis. RESULTS: Both manVMAT and autoVMAT plans were considered clinically acceptable. Target coverage was similar (manVMAT: 96.6 ± 1.6%, autoVMAT: 97.4 ± 1.0%, p = 0.085). With autoVMAT, median kidney dose was reduced on average by > 25%; (for left kidney from 11.3 ± 2.1 Gy to 8.9 ± 3.5 Gy (p = 0.002); for right kidney from 9.2 ± 2.2 Gy to 6.1 ± 1.3 Gy (p <  0.001)). Median dose to the liver was lower as well (18.8 ± 2.3 Gy vs. 17.1 ± 3.6 Gy, p = 0.048). In addition, Dmax of the spinal cord was significantly reduced (38.3 ± 3.7 Gy vs. 31.6 ± 2.6 Gy, p <  0.001). Substantial improvements in dose conformity and integral dose were achieved with autoVMAT plans (4.2% and 9.1%, respectively; p <  0.001). Due to the better OAR sparing in the autoVMAT plans compared to manVMAT plans, the predicted NTCPs for the left and right kidney and the liver-PTV were significantly reduced by 11.3%, 12.8%, 7%, respectively (p ≤ 0.001). Delivery time and total number of monitor units were increased in autoVMAT plans (from 168 ± 19 s to 207 ± 26 s, p = 0.006) and (from 781 ± 168 MU to 1001 ± 134 MU, p = 0.003), respectively. CONCLUSIONS: For postoperative/adjuvant radiotherapy of advanced gastric cancer, involving a complex target shape, automated VMAT planning is feasible and can substantially reduce the dose to the kidneys and the liver, without compromising the target dose delivery.


Subject(s)
Organs at Risk/radiation effects , Radiotherapy Planning, Computer-Assisted/methods , Radiotherapy, Intensity-Modulated/methods , Stomach Neoplasms/radiotherapy , Adjuvants, Immunologic , Humans , Postoperative Period , Prognosis , Radiotherapy Dosage
14.
Strahlenther Onkol ; 194(4): 333-342, 2018 04.
Article in English | MEDLINE | ID: mdl-29270648

ABSTRACT

BACKGROUND: For several tumor entities, automated treatment planning has improved plan quality and planning efficiency, and may enable adaptive treatment approaches. Whole-pelvic prostate radiotherapy (WPRT) involves large concave target volumes, which present a challenge for volumetric arc therapy (VMAT) optimization. This study evaluates automated VMAT planning for WPRT-VMAT and compares the results with manual expert planning. METHODS: A system for fully automated multi-criterial plan generation was configured for each step of sequential-boost WPRT-VMAT, with final "autoVMAT" plans being automatically calculated by the Monaco treatment planning system (TPS; Elekta AB, Stockholm, Sweden). Configuration was based on manually generated VMAT plans (manualVMAT) of 5 test patients, the planning protocol, and discussions with the treating physician on wishes for plan improvements. AutoVMAT plans were then generated for another 30 evaluation patients and compared to manualVMAT plans. For all 35 patients, manualVMAT plans were optimized by expert planners using the Monaco TPS. RESULTS: AutoVMAT plans exhibited strongly improved organ sparing and higher conformity compared to manualVMAT. On average, mean doses (Dmean) of bladder and rectum were reduced by 10.7 and 4.5 Gy, respectively, by autoVMAT. Prostate target coverage (V95%) was slightly higher (+0.6%) with manualVMAT. In a blinded scoring session, the radiation oncologist preferred autoVMAT plans to manualVMAT plans for 27/30 patients. All treatment plans were considered clinically acceptable. The workload per patient was reduced by > 70 min. CONCLUSION: Automated VMAT planning for complex WPRT dose distributions is feasible and creates treatment plans that are generally dosimetrically superior to manually optimized plans.


Subject(s)
Pelvis/radiation effects , Prostatic Neoplasms/radiotherapy , Radiotherapy Planning, Computer-Assisted/methods , Radiotherapy, Intensity-Modulated/methods , Aged , Algorithms , Humans , Lymphatic Metastasis/radiotherapy , Male , Middle Aged , Organs at Risk/radiation effects , Radiotherapy Dosage , Tumor Burden/radiation effects
15.
J Perinatol ; 38(1): 46-53, 2018 01.
Article in English | MEDLINE | ID: mdl-29095432

ABSTRACT

OBJECTIVE: Pregnancy-induced hypertension (PIH) is associated with preterm delivery but its independent impact on neonatal outcomes remains unclear. We sought to systematically review and meta-analyze clinical outcomes of preterm infants <37 weeks' gestation born to mothers with and without PIH. STUDY DESIGN: Medline, Embase, PsychINFO and CINAHL were searched from January 2000 to October 2016. Studies with low-moderate risk of bias reporting neonatal outcomes based on PIH as primary exposure variable were included. Data were extracted independently by two co-authors. RESULTS: PIH was associated with lower mortality (3 studies; adjusted odds ratio (aOR) 0.65; 95% confidence interval (CI) 0.54 to 0.79), lower severe retinopathy of prematurity (ROP) (2 studies; aOR 0.83; 0.72 to 0.96) and lower severe brain injury (2 studies; unadjusted OR (uOR) 0.57; 0.49 to 0.66). No association between PIH and short-term respiratory outcomes, bronchopulmonary dysplasia (BPD) or necrotizing enterocolitis (NEC) was identified. In subgroup analysis among infants <29 weeks' gestation, BPD odds were higher (3 studies; aOR 1.15; 1.06 to 1.26), whereas mortality lower (2 studies; aOR 0.73; 0.69 to 0.77). In subgroup analysis limited to severe PIH, odds of mortality (3 studies; uOR 2.36; 1.07 to 5.22) and invasive ventilation (3 studies; uOR 3.26; 1.11 to 9.61) were higher. In subgroup analysis limited to preeclampsia, odds of BPD (3 studies; uOR 1.21; 95% CI:1.03 to 1.43) and NEC were higher (3 studies; uOR 2.79; 95% CI:1.57 to 4.96). CONCLUSION: PIH was associated with reduced odds of mortality and ROP (all infants), but higher odds for BPD (<29 weeks' gestation). The paradoxical reduction in mortality may be due to survival bias and deserves further exploration in future studies.


Subject(s)
Bronchopulmonary Dysplasia/mortality , Enterocolitis, Necrotizing/mortality , Hypertension, Pregnancy-Induced/epidemiology , Retinopathy of Prematurity/mortality , Female , Gestational Age , Humans , Infant, Extremely Premature , Infant, Newborn , Odds Ratio , Pregnancy
16.
Microb Genom ; 3(8): e000120, 2017 08.
Article in English | MEDLINE | ID: mdl-29026659

ABSTRACT

Countries of the African 'meningitis belt' are susceptible to meningococcal meningitis outbreaks. While in the past major epidemics have been primarily caused by serogroup A meningococci, W strains are currently responsible for most of the cases. After an epidemic in Mecca in 2000, W:ST-11 strains have caused many outbreaks worldwide. An unrelated W:ST-2881 clone was described for the first time in 2002, with the first meningitis cases caused by these bacteria reported in 2003. Here we describe results of a comparative whole-genome analysis of 74 W:ST-2881 strains isolated within the framework of two longitudinal colonization and disease studies conducted in Ghana and Burkina Faso. Genomic data indicate that the W:ST-2881 clone has emerged from Y:ST-175(CC175) bacteria by capsule switching. The circulating W:ST-2881 populations were composed of a variety of closely related but distinct genomic variants with no systematic differences between colonization and disease isolates. Two distinct and geographically clustered phylogenetic clonal variants were identified in Burkina Faso and a third in Ghana. On the basis of the presence or absence of 17 recombination fragments, the Ghanaian variant could be differentiated into five clusters. All 25 Ghanaian disease isolates clustered together with 23 out of 40 Ghanaian isolates associated with carriage within one cluster, indicating that W:ST-2881 clusters differ in virulence. More than half of the genes affected by horizontal gene transfer encoded proteins of the 'cell envelope' and the 'transport/binding protein' categories, which indicates that exchange of non-capsular antigens plays an important role in immune evasion.


Subject(s)
Meningitis, Meningococcal/microbiology , Neisseria meningitidis/genetics , Burkina Faso/epidemiology , Disease Outbreaks , Gene Transfer, Horizontal , Ghana/epidemiology , Humans , Meningitis, Meningococcal/epidemiology , Neisseria meningitidis/pathogenicity , Virulence
17.
Radiother Oncol ; 125(3): 507-513, 2017 12.
Article in English | MEDLINE | ID: mdl-29050954

ABSTRACT

BACKGROUND AND PURPOSE: The TRENDY trial is an international multi-center phase-II study, randomizing hepatocellular carcinoma (HCC) patients between transarterial chemoembolization (TACE) and stereotactic body radiation therapy (SBRT) with a target dose of 48-54 Gy in six fractions. The radiotherapy quality assurance (QA) program, including prospective plan feedback based on automated treatment planning, is described and results are reported. MATERIALS AND METHODS: Scans of a single patient were used as a benchmark case. Contours submitted by nine participating centers were compared with reference contours. The subsequent planning round was based on a single set of contours. A total of 20 plans from participating centers, including 12 from the benchmark case, 5 from a clinical pilot and 3 from the first study patients, were compared to automatically generated VMAT plans. RESULTS: For the submitted liver contours, Dice Similarity Coefficients (DSC) with the reference delineation ranged from 0.925 to 0.954. For the GTV, the DSC varied between 0.721 and 0.876. For the 12 plans on the benchmark case, healthy liver normal-tissue complication probabilities (NTCPs) ranged from 0.2% to 22.2% with little correlation between NCTP and PTV-D95% (R2 < 0.3). Four protocol deviations were detected in the set of 20 treatment plans. Comparison with co-planar autoVMAT QA plans revealed these were due to too high target dose and suboptimal planning. Overall, autoVMAT resulted in an average liver NTCP reduction of 2.2 percent point (range: 16.2 percent point to -1.8 percent point, p = 0.03), and lower doses to the healthy liver (p < 0.01) and gastrointestinal organs at risk (p < 0.001). CONCLUSIONS: Delineation variation resulted in feedback to participating centers. Automated treatment planning can play an important role in clinical trials for prospective plan QA as suboptimal plans were detected.


Subject(s)
Benchmarking , Carcinoma, Hepatocellular/radiotherapy , Chemoembolization, Therapeutic , Liver Neoplasms/radiotherapy , Quality Assurance, Health Care , Radiosurgery , Radiotherapy Planning, Computer-Assisted/methods , Humans , Prospective Studies , Radiotherapy Dosage
18.
Radiother Oncol ; 123(1): 49-56, 2017 04.
Article in English | MEDLINE | ID: mdl-28341061

ABSTRACT

PURPOSE: To propose a novel treatment approach, designated VMAT+, involving addition of <5 IMRT beams with computer-optimized non-coplanar orientations to VMAT, and evaluate it for liver Stereotactic Body Radiation Therapy (SBRT). VMAT+ is investigated as an alternative for (1) coplanar VMAT and (2) multi-beam non-coplanar treatment. METHODS/MATERIALS: For fifteen patients with liver metastases, VMAT+ plans were compared with (1) dual-arc VMAT and (2) 25-beam, non-coplanar treatment with computer-optimized beam orientations (25-NCP). All plans were generated fully automatically for delivery of the highest feasible tumor Biologically Effective Dose (BED). OAR doses, intermediate-dose-spillage, dose-compactness, and measured delivery times were evaluated. RESULTS: With VMAT+ the maximum achievable tumor BED was equal to that of 25-NCP. Conversely, VMAT resulted in a lower tumor BED in 5 patients. Compared to VMAT, VMAT+ yielded significant dose reductions in OARs. Intermediate-dose-spillage and dose-compactness were significantly improved by 9.8% and 17.3% (p≤0.002), respectively. Treatment times with VMAT+ were only enhanced by 4.1min on average, compared to VMAT (8.4min). Improvements in OAR sparing with 25-NCP, compared to VMAT+, were generally modest and/or statistically insignificant, while delivery times were on average 20.5min longer. CONCLUSIONS: For liver SBRT, VMAT+ is equivalent to time-consuming treatment with 25 non-coplanar beams in terms of achievable tumor BED. Compared to VMAT, OAR sparing and intermediate-dose-spillage are significantly improved, with minor increase in delivery time.


Subject(s)
Liver Neoplasms/radiotherapy , Radiosurgery/methods , Radiotherapy Planning, Computer-Assisted/methods , Radiotherapy, Intensity-Modulated/methods , Adult , Aged , Aged, 80 and over , Female , Humans , Liver Neoplasms/secondary , Male , Middle Aged , Radiotherapy Dosage , Treatment Outcome
19.
Radiat Oncol ; 12(1): 33, 2017 Jan 31.
Article in English | MEDLINE | ID: mdl-28143623

ABSTRACT

BACKGROUND: Planning for Volumetric Modulated Arc Therapy (VMAT) may be time consuming and its use is limited by available staff resources. Automated multicriterial treatment planning can eliminate this bottleneck. We compared automatically created (auto) VMAT plans generated by Erasmus-iCycle to manually created VMAT plans for treatment of spinal metastases. METHODS: Forty-two targets in 32 patients were analyzed. Lungs and kidneys were defined as organs at risk (OARs). Twenty-two patients received radiotherapy on kidney levels, 17 on lung levels, and 3 on both levels. RESULTS: All Erasmus-iCycle plans were clinically acceptable. When compared to manual plans, planning target volume (PTV) coverage of auto plans was significantly better. The Homogeneity Index did not differ significantly between the groups. Mean dose to OARs was lower in auto plans concerning both kidneys and the left lung. One hotspot (>110% of D50%) occurred in the spinal cord of one auto plan (33.2 Gy, D50%: 30 Gy). Treatment time was 7% longer in auto plans. CONCLUSIONS: Erasmus-iCycle plans showed better target coverage and sparing of OARs at the expense of minimally longer treatment times (for which no constraint was set).


Subject(s)
Neoplasms/radiotherapy , Organs at Risk/radiation effects , Radiotherapy Planning, Computer-Assisted/methods , Radiotherapy, Intensity-Modulated/methods , Spinal Neoplasms/radiotherapy , Automation , Follow-Up Studies , Humans , Neoplasm Staging , Neoplasms/pathology , Prognosis , Radiotherapy Dosage , Spinal Neoplasms/secondary
20.
PLoS One ; 11(12): e0169202, 2016.
Article in English | MEDLINE | ID: mdl-28033342

ABSTRACT

PURPOSE: To develop and validate fully automated generation of VMAT plan-libraries for plan-of-the-day adaptive radiotherapy in locally-advanced cervical cancer. MATERIAL AND METHODS: Our framework for fully automated treatment plan generation (Erasmus-iCycle) was adapted to create dual-arc VMAT treatment plan libraries for cervical cancer patients. For each of 34 patients, automatically generated VMAT plans (autoVMAT) were compared to manually generated, clinically delivered 9-beam IMRT plans (CLINICAL), and to dual-arc VMAT plans generated manually by an expert planner (manVMAT). Furthermore, all plans were benchmarked against 20-beam equi-angular IMRT plans (autoIMRT). For all plans, a PTV coverage of 99.5% by at least 95% of the prescribed dose (46 Gy) had the highest planning priority, followed by minimization of V45Gy for small bowel (SB). Other OARs considered were bladder, rectum, and sigmoid. RESULTS: All plans had a highly similar PTV coverage, within the clinical constraints (above). After plan normalizations for exactly equal median PTV doses in corresponding plans, all evaluated OAR parameters in autoVMAT plans were on average lower than in the CLINICAL plans with an average reduction in SB V45Gy of 34.6% (p<0.001). For 41/44 autoVMAT plans, SB V45Gy was lower than for manVMAT (p<0.001, average reduction 30.3%), while SB V15Gy increased by 2.3% (p = 0.011). AutoIMRT reduced SB V45Gy by another 2.7% compared to autoVMAT, while also resulting in a 9.0% reduction in SB V15Gy (p<0.001), but with a prolonged delivery time. Differences between manVMAT and autoVMAT in bladder, rectal and sigmoid doses were ≤ 1%. Improvements in SB dose delivery with autoVMAT instead of manVMAT were higher for empty bladder PTVs compared to full bladder PTVs, due to differences in concavity of the PTVs. CONCLUSIONS: Quality of automatically generated VMAT plans was superior to manually generated plans. Automatic VMAT plan generation for cervical cancer has been implemented in our clinical routine. Due to the achieved workload reduction, extension of plan libraries has become feasible.


Subject(s)
Radiotherapy Planning, Computer-Assisted/methods , Radiotherapy, Intensity-Modulated , Uterine Cervical Neoplasms/radiotherapy , Automation , Female , Humans , Monte Carlo Method , Radiotherapy Dosage , Time Factors
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