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1.
Environ Monit Assess ; 195(8): 987, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37490169

RESUMO

Qaroun Lake is one of the most important Egyptian lakes which, recently, have been exposed to severe degradation in water quality and fish productivity. In this manuscript, Carlson's trophic state index (CTSI) was used to evaluate the trophic state, while the trophometric index (TMI) was used to assess the potential productivity of Qaroun Lake. The present study is one of the initial attempts to investigate these indices in Qaroun Lake. To achieve this work, an integrated multidisciplinary approach was adopted integrating field investigation, geographic information system, and data analysis. CTSI combines three variables of water quality: chlorophyll-a (CHL-a), total phosphorus (TP), and transparency measured by Secchi disk depth (SDD). The result of overall CTSI showed the hypereutrophic state is represented by 62% and eutrophic state is represented by 38% of the total lake's area. Moreover, the calculated TMI indicated the average potential productivity value (PP) is 619 t. It can be concluded that the hypereutrophic is the dominant state in Qaroun Lake. The present study recommends the application of TMI model to evaluate and monitor the changes in Qaroun Lake's potential productivity in response to the changing environmental conditions and other biological pressures (e.g., Isopoda paraside).


Assuntos
Monitoramento Ambiental , Lagos , Animais , Estado Nutricional , Clorofila A , Egito
2.
Radiat Environ Biophys ; 61(2): 263-277, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35396948

RESUMO

Hypoxia is a condition in which proliferating tumor cells are deprived of oxygen due to limited blood supply from abnormal tumor microvasculature. This study aimed to investigate the molecular changes that occur in tumor cell hypoxia with special emphasis placed on the efficacy of chemotherapeutic and radiation-related effects. Four commercially available chemotherapeutic agents: cisplatin, cyclophosphamide, doxorubicin, and 5-fluorouracil, were tested for their cytotoxic activity on the cancer cell lines PC3 (prostate), HepG2 (liver), and MCF-7 (breast). Tumor cell lines under hypoxia were treated with both IC50 concentrations of the different chemotherapeutic agents and irradiated with 5 and 10 Gy using a 137Cs gamma source. Hypoxia-inducible factor-1α (HIF-1α) protein levels were examined using an ELISA assay. Hypoxic cells showed a significant change in cell viability to all chemotherapeutic agents in comparison to normoxic controls. HepG2 cells were more resistant to the cytotoxic drug doxorubicin compared to other cancer cell lines. The flow cytometric analysis showed that hypoxic cells have lower levels of total apoptotic cell populations (early and late apoptosis) compared to normoxic cells suggesting decreased hypoxia-induced apoptosis in cancer cells. The highest reduction in HIF-1α level was observed in the MCF-7 cell line (95.5%) in response to the doxorubicin treatment combined with 10 Gy irradiation of cells. Chemoradiotherapy could result in minimal as well as a high reduction of HIF-1α based on cell type, type of chemotherapy, and amount of ionizing radiation. This study highlights future research work to optimize a combined chemoradiotherapeutic regime in individual cancer cell hypoxia.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Humanos , Hipóxia , Masculino , Doses de Radiação , Hipóxia Tumoral
3.
Pol J Radiol ; 85: e586-e594, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33204373

RESUMO

PURPOSE: To explore whether radiomic features of fluorine-18-fluorodeoxyglucose (18F-FDG) positron emission tomo-graphy-computed tomography (PET/CT) has association with bone marrow infiltration (BMI) in comparison to other conventional PET metrics. MATERIAL AND METHODS: Forty-four patients (with pathologically proven lymphoma disease) underwent staging 18F-FDG PET/CT scan. Primary tumour was semi-automatically or manually segmented with a threshold standardised uptake value (SUV) of 3. A total of 73 features were extracted from eight different textures. Spearman correlation was used to test the correlation of features with conventional quantitative metrics such as SUV, metabolic tumour volume, and total lesion glycolysis. Specificity and sensitivity (including 95% confidence intervals [CI]) for each of the studied parameters were derived using receiver operative characteristic (ROC) curves. Univariate and multivariate analyses were used to identify independent predictors associated with BMI. RESULTS: Correlation between conventional PET metrics and features ranged between 0.50 and 0.97 for positive correlation (33 significant association features) and ranged from -0.52 to -0.97 for inverse correlation (three significant association features) for both strong and moderate correlations. Analysis of ROC curves showed that high-intensity long-run emphasis 4 bin, high-intensity large zone emphasis 64 bin, long-run emphasis (LRE) 64 bin, large-zone emphasis 64 bin, max spectrum 8 bin, busyness 64 bin, and code similarity 32 and 64 bin were significant discriminators of BMI among other features (area under curve > 0.682, p < 0.05). Univariate analyses of texture features showed that code similarity and long-run emphasis (both 64 bin) were significant predictors of bone marrow involvement. Multivariate analyses revealed that LRE (64 bin, p = 0.031) with an odds ratio of 1.022 and 95% CI of (1.002-1.043) were independent variables for bone marrow involvement. CONCLUSIONS: 18F-FDG PET/CT radiomic features are synergistic to visual assessment of BMI in patients diagnosed with lymphoma using 18F-FDG PET/CT. Further assessment of long-run emphasis is highly warranted.

4.
Transfus Med Hemother ; 45(6): 404-412, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30574058

RESUMO

BACKGROUND: Hypercoagulability can lead to serious thromboembolic events. The aim of this study was to assess the perioperative coagulation status in liver transplant recipients with a tendency to hypercoagulability. METHODS: In a prospective observational study (South African Cochrane Registry 201405000814129), 151 potential liver transplant recipients were screened for thrombophilic factors from October 2014 to June 2017, and 57 potential recipients fulfilled the inclusion criterion of presenting two or more of the following thrombophilic factors: low protein C, low protein S, low anti-thrombin, increased homocystein, increased antiphospholipid IgG/IgM antibodies, increased lupus anticoagulant, and positive Factor V Leiden mutation. Seven patients were excluded from the study because they fulfilled the exclusion criteria of cancelling the liver transplantation, oral anticoagulation, or intraoperative treatment with rFVIIa. Accordingly, 50 patients were included in the final analysis. Thromboelastometry (ROTEM) (EXTEM, INTEM and FIBTEM) and conventional coagulation tests (CCT) were performed preoperatively, during the anhepatic phase, post reperfusion, and on postoperative days (POD) 1, 3 and 7. ROTEM was used to guide blood product transfusion. Heparin was infused (60-180 U/kg/day) postoperatively for 3 days and then was replaced by low-molecular-weight heparin (20 mg/12 h). RESULTS: FIBTEM MCF significantly increased postoperatively above reference range on POD 7 despite normal fibrinogen plasma concentrations (p < 0.05). Both EXTEM and INTEM demonstrated significant changes with the phases of transplantation (p < 0.05), but with no intra- or postoperative hypercoagulability observed. INTEM CT (reference range, 100-240 s) normalized on POD 3 and 7 (196.1 ± 69.0 and 182.7 ± 63.8 s, respectively), despite prolonged aPTT (59.7 ± 18.7 and 46.4 ± 15.7 s, respectively; reference range, 20-40 s). Hepatic artery thrombosis (HAT) and portal vein thrombosis (PVT) were reported in 12.0% and 2.0%, respectively, mainly after critical care discharge and with high FIBTEM MCF values in 57% on POD 3 and 86% on POD 7. Receiver operating characteristics curve analyses of FIBTEM MCF were significant predictors for thromboembolic events with optimum cut-off, area under the curve and standard error on POD 3 (>23 mm, 0.779 and 0.097; p = 0.004) and POD 7 (>28 mm, 0.706 and 0.089; p = 0.020). Red blood cells (mean ± SD, 8.68 ± 5.81 units) were transfused in 76%, fresh frozen plasma (8.26 ± 4.14 units) in 62%, and cryoprecipitate (12.0 ± 3.68 units) in 28% of recipients. None of the recipients received intraoperative platelet transfusion or any postoperative transfusion. Main transplant indication was hepatitis C infection in 82%. 76% of recipients included in this highly selected patient population showed increased lupus anticoagulant, 2% increased antiphospholipid IgG/IgM antibodies, 20% increased homocysteine, 74% decreased anti-thrombin, 78% decreased protein C, 34% decreased protein S, and 24% a positive Factor V Leiden mutation. Overall 1-year survival was 62%. CONCLUSION: A significant postoperative step-wise increase in FIBTEM MCF beyond the reference range was observed despite normal fibrinogen plasma concentrations, and FIBTEM MCF was a predictor for thromboembolic events in this study population, particularly after POD 3 and 7 on surgical wards when CCTs failed to detect this condition. However, the predictive value of FIBTEM MCF for postoperative HAT and PVT needs to be confirmed in a larger patient population. A ROTEM-guided anticoagulation regime needs to be developed and investigated in future studies.

5.
Int J Phytoremediation ; 19(11): 1023-1028, 2017 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-28436685

RESUMO

The effect of hydraulic loading rate (HLR) and hydraulic retention time (HRT) on the bioremediation of municipal wastewater using a pilot scale subsurface horizontal flow constructed treatment wetland (HFCTW) vegetated with Cyprus papyrus was investigated. Different HLRs were applied to the treatment system namely 0.18, 0.10, and 0.07 m3/m2. d with corresponding HRTs of 1.8, 3.2, and 4.7 days, respectively. The flow rate was 8 m3/d, and the average organic loading rate (OLR) was 0.037 kg BOD/m3/d. Results showed that the performance of the HFCTW was linearly affected by decreasing the HLR and increasing the HRT. The highest treatment efficiency was achieved at HRT (4.7 days) and HLR (0.07 m3/m2. d). The percentage reductions of chemical oxygen demand (COD), biochemical oxygen demand (BOD), and total suspended solids (TSS) were 86%, 87%, and 80%, respectively. Satisfactory nutrient removal was obtained. Also, removal of 2-3 logs of bacterial indicators of pollution was achieved. The dry biomass of Cyperus was 7.7 kg/m2 and proved to be very efficient in nitrification processes due to high diversity of the roots that increase the treatment surface area.


Assuntos
Biodegradação Ambiental , Cyperus , Águas Residuárias , Áreas Alagadas , Biomassa
6.
Mol Imaging ; 132014.
Artigo em Inglês | MEDLINE | ID: mdl-24825602

RESUMO

Noninvasive imaging methods are required to monitor the inflammatory content of atherosclerotic plaques. FEDAA1106 (N-(5-fluoro-2-phenoxyphenyl)-N-(2-(2-fluoroethoxy)-5-methoxybenzyl) acetamide) is a selective ligand for TSPO-18kDa (also known as peripheral benzodiazepine receptor), which is expressed by activated macrophages. We compared 18F-FEDAA1106 and 2-deoxy-2-[18F]fluoro-d-glucose (18F-FDG, a marker of glucose metabolism) for positron emission tomographic (PET) imaging of vascular inflammation. This was tested using a murine model in which focal inflammation was induced in the carotid artery via placement of a constrictive cuff. Immunostaining revealed CD68-positive cells (macrophages) at a disturbed flow site located downstream from the cuff. Dynamic PET imaging using 18F-FEDAA1106 or 18F-FDG was registered to anatomic data generated by computed tomographic (CT)/CT angiography. Standardized uptake values were significantly increased at cuffed compared to contralateral arteries using either 18F-FEDAA1106 (p < .01) or FDG (p < .05). However, the 18F-FEDAA1106 signal was significantly higher at the inflamed disturbed flow region compared to the noninflamed uniform flow regions, whereas differences in FDG uptake were less distinct. We conclude that 18F-FEDAA1106 can be used in vivo for detection of vascular inflammation. Moreover, the signal pattern of 18F-FEDAA1106 corresponded with vascular inflammation more specifically than FDG uptake.


Assuntos
Acetamidas , Artérias Carótidas/patologia , Fluordesoxiglucose F18 , Placa Aterosclerótica/diagnóstico , Compostos Radiofarmacêuticos , Acetamidas/metabolismo , Animais , Modelos Animais de Doenças , Fluordesoxiglucose F18/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Placa Aterosclerótica/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos/metabolismo
7.
Platelets ; 25(8): 576-86, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24246132

RESUMO

Platelet transfusion (PTx) has been identified as an important risk factor for morbidity and mortality after liver transplantation (LTx). Our aim was to evaluate the safety of therapeutic rather than prophylactic PTx policy in severe thrombocytopenic patients undergoing LTx. Recipients of LTx were divided into two groups: group I (GI) (n = 76) platelet count (PC) ≥ 50 × 10(9)/l and group II (GII) PC < 50 × 109/l (n = 76). Platelets were transfused following a thromboelastometry protocol and clinical signs of diffuse bleeding. Both groups were compared regarding hemoglobin (Hb), international normalized ratio (INR), fibrinogen level, blood loss (BL), blood products required, percentage of bloodless surgery, duration of mechanical ventilation, ICU stay, and vascular complications. Each group was further subdivided according to PTx into (GI NPTx and GII NPTx) with no platelet transfusion (NPTx) and (GI PTx and GII PTx) received PTx. These subgroups were further compared for some variables. Base line Hb was significantly higher while INR was significantly lower in GI.75% avoided PTx in GII. Comparisons of BL, packed red blood cells (PRBCs), and cryoprecipitate transfusion were insignificant. Fresh frozen plasma (FFP) transfusion was higher and the percentage of bloodless surgery was lower in GII. In GII, PC increased after start of surgery. Two cases of hepatic artery thrombosis in GI and one in GII were recorded. Recovery of platelets was quicker, and duration of mechanical ventilation and ICU stay was shorter in NPTx patients regardless the base line PC. Cut-off values of PC 30 × 10(9)/l (with sensitivity 73.7% and specificity 78.8%, p < 0.01), BL of 3750 ml in GI (sensitivity of 75% and specificity of 69%, p < 0.01) and of 3250 ml in GII (sensitivity of 84.2% and specificity of 87.7% (p < 0.01)) could indicate the need of PTx. With therapeutic approach, 75% of patients in GII could avoid unnecessary PTx with its hazards without excessive bleeding. PC in GII increased intraoperatively, PTx may lead to delayed recovery of platelets, increased duration of mechanical ventilation and ICU stay. The given cut-off values may help to guide PTx.


Assuntos
Transplante de Fígado/efeitos adversos , Transfusão de Plaquetas/métodos , Trombocitopenia/terapia , Adulto , Feminino , Humanos , Masculino , Fatores de Risco
8.
J Genet Eng Biotechnol ; 22(1): 100336, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38494248

RESUMO

BACKGROUND: The Nonstructural Protein (NSP) 4B of Zika virus of 251 amino acids from (ZIKV/Human/POLG_ZIKVF) with accession number (A0A024B7W1), Induces the production of Endoplasmic Reticulum ER-derived membrane vesicles, which are the sites of viral replication. To understand the physical basis of how proteins fold in nature and to solve the challenge of protein structure prediction, Ab-initio and comparative modeling are crucial tools. RESULTS: The systematic in silico technique, ThreaDom, had only predicted one domain (4 - 190) of NSP4B. I-TASSER, and Alphafold were ranked as the best servers for full-length 3-D protein structure predictions of NSP4B, where the predicted models were evaluated quantitatively using benchmarked metrics including C-score (-3.43), TM-score (0.77949), RMSD (2.73), and Z-score (1.561). The functional and protein binding motifs were realized using motif databases, secondary and surface accessibility predictions combined with Post-Translational Modification Sites (PTMs) prediction. Two highly conserved protein-binding motifs (Flavi NS4B and Bacillus papRprotein), together with three (PTMs) (Casein Kinase II, Myristyl site, and ASN-Glycosylation site) were predicted utilizing the Motif scan and Scanprosite servers. These patterns and PTMs were associated with NSP4B's role in triggering the development of the viral replication complex and its participation in the localization of NS3 and NS5 on the membrane. Only one hit from Structural Classification of Protein (SCOP) matched the protein sequence at positions 10 to 397 and was categorized six-hairpin glycosidases superfamily according to CATH (Class, Architecture, Topology, and Homology). Integrating this NSP4B information with the templates' SCOP and CATH annotations achieves it easier to attribute structure-function/evolution links to both previously known and recently discovered protein structures.

9.
Circ Res ; 108(8): 950-9, 2011 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-21350211

RESUMO

RATIONALE: The nuclear factor (NF)-κB pathway is involved in arterial inflammation. Although the signaling pathways that regulate transcriptional activation of NF-κB are defined, the mechanisms that regulate the expression levels of NF-κB transcription factors are uncertain. OBJECTIVE: We studied the signaling mechanisms that regulate RelA NF-κB subunit expression in endothelial cells (ECs) and their role in arterial inflammation. METHODS AND RESULTS: Gene silencing and chromatin immunoprecipitation revealed that RelA expression was positively regulated by c-Jun N-terminal kinase (JNK) and the downstream transcription factor ATF2 in ECs. We concluded that this pathway promotes focal arterial inflammation as genetic deletion of JNK1 reduced NF-κB expression and macrophage accumulation at an atherosusceptible site. We hypothesized that JNK signaling to NF-κB may be controlled by mechanical forces because atherosusceptibility is associated with exposure to disturbed blood flow. This was assessed by positron emission tomography imaging of carotid arteries modified with a constrictive cuff, a method that was developed to study the effects of disturbed flow on vascular physiology in vivo. This approach coupled to en face staining revealed that disturbed flow elevates NF-κB expression and inflammation in murine carotid arteries via JNK1. CONCLUSIONS: We demonstrate that disturbed blood flow promotes arterial inflammation by inducing NF-κB expression in endothelial cells via JNK-ATF2 signaling. Thus, our findings illuminate a novel form of JNK-NF-κB crosstalk that may determine the focal nature of arterial inflammation and atherosclerosis.


Assuntos
Aorta/metabolismo , Endotélio Vascular/patologia , Regulação Enzimológica da Expressão Gênica , Mediadores da Inflamação/fisiologia , Proteína Quinase 8 Ativada por Mitógeno/biossíntese , NF-kappa B/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Fator de Transcrição RelA/biossíntese , Animais , Aorta/patologia , Aorta/fisiopatologia , Células Cultivadas , Endotélio Vascular/metabolismo , Humanos , Mediadores da Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína Quinase 8 Ativada por Mitógeno/deficiência , Proteína Quinase 8 Ativada por Mitógeno/genética , Fluxo Sanguíneo Regional/genética , Resistência ao Cisalhamento/fisiologia , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/fisiologia , Regulação para Cima/genética
10.
Clin Transplant ; 27(2): E101-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23330941

RESUMO

PURPOSE: To study coagulation of live liver donors with standard coagulation tests (SCT) and rotational thromboelastometry (ROTEM) and investigate their relationship. METHODS: A descriptive prospective study involving 50 right hepatotomy donors with epidural catheters. ROTEM (EXTEM, INTEM, and FIBTEM represent extrinsic and intrinsic pathways of coagulation and fibrinogen activity, respectively) was measured perioperatively and on days 1, 3, 5, 10, and 30. SCTs include prothrombin time (PT), international normalized ratio (INR) of PT, activated partial thromboplastin time (aPPT), fibrinogen, and platelets. RESULTS: PT and INR reflect hypocoagulability reaching maximum on day one (16.9 ± 2.5 s, 1.4 ± 0.2, p < 0.05 compared with baseline). ROTEM was in normal ranges till day 30 with no hypercoagulability. Fibrinogen showed no correlation with maximum clot firmness (MCF) of FIBTEM (r = 0.35, p > 0.05). CFT of EXTEM was not in significant correlation with PT and INR (r = 0.16, 0.19, p > 0.05), respectively. Significant correlation between platelets and both MCF (EXTEM; r = 0.59, p = 0.004) and MCF (INTEM; r = 0.48, p = 0.027). CONCLUSION: ROTEM disagreed with SCTs and did not show the temporary hypocoagulability suggested by SCTs. Both ROTEM and SCTs showed no signs of hypercoagulability. Future studies involving ROTEM could help develop new guidelines for coagulation monitoring.


Assuntos
Transtornos da Coagulação Sanguínea/diagnóstico , Hepatectomia , Transplante de Fígado , Doadores Vivos , Complicações Pós-Operatórias/diagnóstico , Tromboelastografia/métodos , Trombofilia/diagnóstico , Adulto , Transtornos da Coagulação Sanguínea/sangue , Transtornos da Coagulação Sanguínea/etiologia , Testes de Coagulação Sanguínea , Estudos Transversais , Feminino , Humanos , Masculino , Avaliação de Resultados em Cuidados de Saúde , Complicações Pós-Operatórias/sangue , Estudos Prospectivos , Trombofilia/sangue , Trombofilia/etiologia
11.
Insights Imaging ; 14(1): 91, 2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37199791

RESUMO

OBJECTIVES: This study aimed to explore and develop artificial intelligence approaches for efficient classification of pulmonary nodules based on CT scans. MATERIALS AND METHODS: A number of 1007 nodules were obtained from 551 patients of LIDC-IDRI dataset. All nodules were cropped into 64 × 64 PNG images , and preprocessing was carried out to clean the image from surrounding non-nodular structure. In machine learning method, texture Haralick and local binary pattern features were extracted. Four features were selected using principal component analysis (PCA) algorithm before running classifiers. In deep learning, a simple CNN model was constructed and transfer learning was applied using VGG-16 and VGG-19, DenseNet-121 and DenseNet-169 and ResNet as pre-trained models with fine tuning. RESULTS: In statistical machine learning method, the optimal AUROC was 0.885 ± 0.024 with random forest classifier and the best accuracy was 0.819 ± 0.016 with support vector machine. In deep learning, the best accuracy reached 90.39% with DenseNet-121 model and the best AUROC was 96.0%, 95.39% and 95.69% with simple CNN, VGG-16 and VGG-19, respectively. The best sensitivity reached 90.32% using DenseNet-169 and the best specificity attained was 93.65% when applying the DenseNet-121 and ResNet-152V2. CONCLUSION: Deep learning methods with transfer learning showed several benefits over statistical learning in terms of nodule prediction performance and saving efforts and time in training large datasets. SVM and DenseNet-121 showed the best performance when compared with their counterparts. There is still more room for improvement, especially when more data can be trained and lesion volume is represented in 3D. CLINICAL RELEVANCE STATEMENT: Machine learning methods offer unique opportunities and open new venues in clinical diagnosis of lung cancer. The deep learning approach has been more accurate than statistical learning methods. SVM and DenseNet-121 showed superior performance in pulmonary nodule classification.

12.
J Med Imaging Radiat Sci ; 54(3): 473-480, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37481373

RESUMO

BACKGROUND: Volumetric Modulated Arc Therapy (VMAT) is an option for the delivery of Radiotherapy treatment technique for pediatric nasopharyngeal cancer, VMAT is the most common treatment technique for pediatric nasopharyngeal cancer. The use of a combination of both biological and physical parameters in VMAT planning optimization may produce better target coverage and sparing of critical organs. This work was to compare Biological Cost Functions (BCFs) and Physical Cost Functions (PCFs) in the VMAT of pediatric nasopharyngeal cancer patients. METHOD: VMAT plans for 20 nasopharyngeal pediatric cancer patients were created using Monaco 5.11® treatment planning system (TPS). Three VMAT plans were retrospectively generated for each patient using BCFs, PCFs and mixed plan with a total dose of 61.2 Gy in 34 fractions to planning target volume (PTV). All plans were adjusted to deliver 95% of the prescribed dose to 95% of the PTV. The calculated plans were qualitatively and quantitatively evaluated using the dose-volume histogram (DVH). RESULTS: The coverage of the target and the maximum dose for the three plans were nearly the same, and better sparing was achieved in the serial organs (spinal cord and brain stem) with PCFs. On the contrary, more dose spring was observed using the BCFs in the organs at risk (OARs) that were not involved in the dose optimization, such as the optic nerve maximum dose, with a significant p-value (0.035 and 0.0001) respectively. Using the PCFs, both parotids received a lower mean dose, but not for the oral cavity, which had a lower mean dose using BCFs (p=<0.0001). The same values of tumor control probability (TCP) were found for both cost functions in PTVs and normal tissue complications probability (NTCP) (99%). The values reported were as follows: spinal cord = 0.5%, brain stem = 19.1%, and brain = 90.7% for BCFs, compared to spinal cord = 0.3%, brain stem = 14.9%, and brain = 90.7% for PCFs. The delivery time was found to be less in BCFs (p=0.005). CONCLUSION: The BCFs are superior to the PCFs in conformity index and time of radiation delivery. However, PCFs were better at dose sparing for the serial organs and achieving a sharper falloff dose around the involved volumes. A patient-specific clinical compromise is recommended to gain the best plan that meets the clinical goals.


Assuntos
Neoplasias Nasofaríngeas , Radioterapia de Intensidade Modulada , Humanos , Criança , Neoplasias Nasofaríngeas/radioterapia , Estudos Retrospectivos , Encéfalo , Órgãos em Risco
13.
Environ Sci Pollut Res Int ; 30(11): 28803-28817, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36402879

RESUMO

Macrobenthic invertebrate communities serve as markers of anthropogenic stress in freshwater ecosystems. In this study, 17 sampling sites were selected from two Nile river subbranches (El-Rayah El-Behery and El-Rayah El-Nassery) and subjected to different anthropogenic influences to explore the ecological environment and characteristics of macrobenthos communities. Macrobenthos were studied using taxonomic diversity and biological trait analysis to investigate how human activity and variation in water quality affect their structure and function. A total of 37 taxa represented by 43,389 individuals were recognized. The communities are composed chiefly of Oligochaeta and aquatic insects. Multivariate statistical analyses found that the most influential environmental variables in the structural and functional community were sodium, dissolved oxygen, silicate, pH, calcium, and cadmium. At high levels of pollution, notably sewage and industrial pollution in the northern part of El-Rayah El-Behery, characteristics such as larger body size, detritus feeders, burrowers, and high tolerance to pollution predominated, whereas at low levels of pollution, features such as small body sizes, scraper and predator feeders, intolerant and fairly tolerant of pollution, and climber and swimmer mobility are predominant. The results confirm our prediction that the distribution of macroinvertebrate traits varies spatially in response to environmental changes. The diversity-based method distinguished impacted sewage and industrial sites from thermal effluent sites, while the trait-based approach illustrated an apparent variance between the ecological status of contaminated regions. Therefore, the biological features should be employed in addition to structural aspects for assessing the biodiversity of macroinvertebrate communities under environmental stressors.


Assuntos
Ecossistema , Oligoquetos , Animais , Humanos , Rios/química , Egito , Esgotos , Monitoramento Ambiental , Invertebrados , Biodiversidade , Qualidade da Água
14.
Eur J Hybrid Imaging ; 6(1): 22, 2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36224438

RESUMO

AIM: This work aims to study the impact of different SUV variants in terms of mean and maximum measures as well as various normalization methods with respect to body weight, body mass index, body surface area, and lean body mass in patients with lymphoma. METHODS: Sixty-nine patients (34 male-35 female) were retrospectively selected. All patients had undergone F18-FDG PET/CT using the standard imaging protocol. In the first part of this study, SUVmean and SUVmax of patients' lesions and three background sites including liver, aorta, and muscle were determined. Then, the normalization of lesion SUV to body weight and body background sites was performed. The ratio of lesion SUVmax to body background sites (muscle, aorta, and liver) SUVmax was determined in addition to the ratio of lesion SUVmean to body background sites SUVmean. The second part of the study included the calculations of the body mass index (BMI), body surface area (BSA), and lean body mass (LBM). The normalization of lesion, liver, aorta, and muscle SUV to BMI, BSA, and LBM was calculated and compared to each other. RESULTS: After performing the appropriate statistical calculations, the results showed that there is a significant difference in SUV measurements between the three background sites. Lesions normalized to the liver were significantly lower than those normalized to aorta and muscle and the results also showed a higher magnitude of lesions normalized to muscle in comparison to the aorta. The SUVmax and SUVmean normalized to different body weight indices showed the lowest variation with BSA and BMI while being increasingly higher with lean body mass using the two methods James and Janmahasatian, respectively, and then highest with body weight. CONCLUSION: The SUVmax and SUVmean showed lower variance in comparison to other background regions. Less variation was also remarkable in SUVmean normalized to BSA and Janma lean mass and also when SUVmax is normalized to James lean body mass. The SUVmax normalized to lean (i.e., James) as well as SUVmean normalized to lean (i.e., Janma) and BSA showed a significant independence with body weight.

15.
Local Reg Anesth ; 15: 1-10, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35115825

RESUMO

BACKGROUND: Hepatic resection is a major abdominal surgery with challenging pain management. We aimed to investigate the effect of erector spinae plane block (ESPB) with opioid free anesthesia (OFA) in cirrhotic patients scheduled for liver resection on perioperative pain management in terms of hemodynamic stability. Secondarily, we assessed time to first request for analgesia and perioperative fentanyl consumption, nausea and vomiting within 24 hours after surgery. METHODS: Forty patients were randomized to block group (n = 20): OFA with ESPB and conventional group (n = 20): conventional balanced anesthesia with opioids (OFA associated non-opioid drugs [dexmedetomidine, magnesium sulfate, xylocaine, and acetaminophen] and ESPB). Bilateral ESP block was done with ultrasound guidance at the level of thoracic vertebrae T 6-7, the local anesthetic dose was 20 mL Bupivacaine 0.25% with adjuvant dexmedetomidine (0.5 µg/kg) on each side. We monitored hemodynamic stability as the primary endpoint (heart rate, mean arterial blood pressure, and cardiac output). RESULTS: Bilateral ESPB offered somatic and visceral analgesia for hepatic resection patients with no intraoperative fentanyl required. Postoperatively, the block group with dexmedetomidine adjuvant to the local anesthesia drugs showed delay in the first request for analgesia (p = 0.092) and decreased fentanyl requirement (p < 0.001), so no patient in the ESP group suffered from postoperative nausea and vomiting compared to 50% in the conventional group (p < 0.001). CONCLUSION: Bilateral ESP block with OFA is an effective approach for intra- and postoperative analgesia in cirrhotic patients undergoing liver resection.

16.
Appl Radiat Isot ; 187: 110305, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35688071

RESUMO

BACKGROUND: This work was carried out to compare the modifying roles of ascorbic and metformin during Ehrlich (ESC) tumor-bearing mice irradiation. METHODS: Fifty Swiss albino male mice were segmented into seven groups, including one control group and six Ehrlich induced tumors treated with ascorbic, ascorbic plus radiation, metformin, metformin plus radiation, and radiation only. Many tests, including behavioral, biochemical, immunohistochemistry, gene expression, DNA fragmentation, oxidative stress markers, and EPR, were performed to interrogate the modifying effects on tumor and liver tissues. RESULTS: Remarkable apoptosis was found in metformin irradiated animals compared to irradiated ascorbic counterparts. The irradiated metformin mice showed the greatest reduction in PCNA. There was a significant reduction of DNA fragmentation in the liver tissues of the irradiated metformin group. Irradiated metformin and irradiated ascorbic acid animals showed a reduced signal of ERK as well as c-Fos genes. There was a tendency of metformin and metformin irradiated animals to reduce MDA levels in liver tissues. ESC-bearing mice treated with ascorbic or metformin showed an improvement in the spontaneous alternation percentage (SAP%) and improved short-term memory. There was also an improvement in long memory tests. CONCLUSIONS: The study added more preclinical evidence on the utility of metformin in cancer treatment during radiotherapy. Metformin was shown to reduce lipid peroxidation in irradiated healthy tissues, increase tumor cytotoxicity, downregulate critical pathways involved in tumor progression and proliferation, and enhance tumor apoptosis. Controlled clinical trials using metformin are highly warranted.


Assuntos
Carcinoma de Ehrlich , Metformina , Neoplasias , Animais , Ácido Ascórbico/farmacologia , Ácido Ascórbico/uso terapêutico , Carcinoma de Ehrlich/tratamento farmacológico , Carcinoma de Ehrlich/radioterapia , Peroxidação de Lipídeos/efeitos da radiação , Metformina/uso terapêutico , Camundongos
17.
Curr Radiopharm ; 15(4): 320-326, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35422232

RESUMO

BACKGROUND: Nuclear medicine or diagnostic radiology personnel are always exposed to low-level radiation from radionuclides used in medical diagnostics, which lead to potential biological hazards or effects. OBJECTIVE: External exposure for workers in two nuclear medicine centers was measured by recruiting 120 patients. METHODS: Three nuclear medicine examinations were performed using F18-FDG PET/CT,99mTc- MDP bones scan, and 99mTc thyroid scan by a digital radiation dosimeter. RESULTS: The average received accumulative radiation dose for workers was found to be 0.838±0.17, 0.527±0.11, and 0.270±0.05 µSv for F18-FDG PET/CT, 99mTc-MDP bones scan, and 99mTc thyroid scan, respectively. The annual effective dose for workers was estimated to be 2.09±0.42, 1.34±0.27, and 0.68±0.14 mSv, respectively. Moreover, the average patient-to-staff dose coefficients were found to be 0.024±0.005, 0.003±0.001, and 0.007±0.002 µSv m2/MBq h for F18- FDG PET/CT, 99mTc-MDP bones scan, and 99mTc thyroid scan, respectively. CONCLUSION: It is clear from the results that the radiation doses received by workers during the nuclear medicine imaging examinations were less than the doses recommended by the International Commission on Radiological Protection (ICRP) for such examinations.


Assuntos
Medicina Nuclear , Exposição à Radiação , Humanos , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Compostos Radiofarmacêuticos
18.
Adv Radiat Oncol ; 7(5): 100905, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35465630

RESUMO

Purpose: Conformity indices (CI) and homogeneity indices (HI) are important tools for evaluating treatment plan quality. In this study, we evaluate the consistency of these indices with respect to anatomic changes undergone by patients. Methods and Materials: Fifty-five patients with advanced head and neck cancer were treated with simultaneous integrated boost volumetric modulated arc therapy. The initial plan (iplan) then was projected on the new computed tomographs (CT) and 2 adaptive plans (Aplans) for each patient were performed on the new CTs. A comparison of CI and HI between the iplan, hybrid plan (Hplan), and Aplan was performed. Results: There was a significant weight loss (P < .001) between CT1, CT2, and CT3, where the median weight at CT1 was 75.78 (68.95-83.42) kg, and 74.88 (68.35-82.2) kg at CT2 and 73.1 (67.6-80.7) kg at CT3. Also, gross tumor volume (GTV) showed significant decrease at CT1, CT2, and CT3. The initial GTV was 32.3 (21-58.6) cc and 28.24 (15.85-48.63) cc at CT2 and 25.12 (14.1-42.2) at CT3. In addition, there was a significant decrease in left parotid volume after 10 and 20 fractions; the median left parotid gland volume at CT1 was 31.04 (26.34-36.27) cc, then was 25.84 (19.19-28.59) cc after 10 fractions and 19.5 (13.53-22.25) cc after 20 fractions; the median right parotid volume at CT1 was 29.81 (24.6-38.75) cc and 22.38 (18.19-30.12) cc at CT2, then the volume fell to 17.74 (13.41-22.66) cc at CT3. Also, a significant increase in dose to organs at risk were noticed at Hplans, the median dose for brain stem at iplan was 5156 (4561-5324) cGy then increased to 5321 (4688-5545) cGy at Hplan1 then increased again to reach 5401 (4821-5812) cGy at Hplan2. The CI showed regression at Hplan1 and Hplan2 and then improvement at Aplan1 and Aplan2. The HI also showed regression in its value at the Hplans and then improved at the Aplans. Conclusions: Based on the results, we conclude that anatomic changes such as weight loss greatly affect the quality of plan, and with Aplans, we maintained the quality of plan by sustaining the values of CI and HI as in the iplan.

19.
Materials (Basel) ; 15(12)2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35744366

RESUMO

The present work is concerned with assessing the cancer risk contributed by the studied granite types including valuable metals, such as Cu, Au, and Ba mineralization, as well as radioactive-bearing mineralization, such as monazite and zircon, in south Monqul at Wadi Makhrag El Ebel, north Eastern Desert, Egypt. The mineralization analyses illustrated that copper mineralization containing chrysocolla and tenorite minerals were restricted to the alteration zone, especially (argillic, phyllic, and propylitic) in monzogranite. However, barite veinlets had an ENE-WSW trend, while gold mineralization was confined to quartz veins having NE-SW trends. Monazite and zircon are radioactive-bearing minerals recorded in monzogranite causing high radioactive zones in south Monqul. The radionuclide activity concentrations were detected in the studied monzogranites. The mean values of AU (103 ± 91 Bq kg-1), ATh (78 ± 19 Bq kg-1), and AK (1484 ± 334 Bq kg-1) in the monzogranite samples were higher than the recommended worldwide average. The change in radioactive-transporting minerals found inside granite faults caused the high amounts of radioactivity seen in the samples. Due to the monzogranites being applied in building materials, the radiological hazards were assessed by calculating risk indices such as annual effective dose (AED) and excess lifetime cancer risk (ELCR). The acceptable limit for the ELCR readings was surpassed. As a result, the investigated monzogranite samples are not suitable for use in infrastructure materials.

20.
Appl Radiat Isot ; 188: 110413, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35994917

RESUMO

The present work aims to study gamma rays emitted by radionuclides such as 238U, 232Th and 40K from acidic Monqul volcanics. The studied volcanics are represented by a thick stratified lava flows interbanded with their pyroclastics. They are composed of thick lava flows of andesite and, to a lesser extent of basalt, and acidic volcanics including rhyolite and dacite. The average values of 238U, 232Th and 40K are (46 ± 24 Bq kg-1), (62 ± 11 Bq kg-1) and (1227 ± 318 Bq kg-1) in the rhyolite-dacite samples are greater than the worldwide average. The variation of radioactive bearing minerals observed inside granite faults produced the great amounts of radioactivity perceived in the samples. Calculating radiological risks is used to assess the public's radioactive risk from radionuclides revealed in the studied Rhyolite-dacite samples. The acceptable limit for excess lifetime cancer (ELCR) evaluations has been exceeded. As a result, Rhyolite-dacite are inappropriate for apply in building materials.


Assuntos
Monitoramento de Radiação , Radioatividade , Rádio (Elemento) , Poluentes Radioativos do Solo , Egito , Radioisótopos de Potássio/análise , Monitoramento de Radiação/métodos , Radioisótopos/análise , Rádio (Elemento)/análise , Medição de Risco , Poluentes Radioativos do Solo/análise , Tório/análise
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