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1.
Nat Commun ; 14(1): 7276, 2023 Nov 10.
Article in English | MEDLINE | ID: mdl-37949855

ABSTRACT

As a universal structure in space plasma, electron holes represent an obvious signature of nonlinear process. Although the theory has a 60-year history, whether electron hole can finally accelerate ambient electrons (or ions) is quite controversial. Previous theory for one-dimensional holes predicts that net velocity change of passing electrons (or ions) occurs only if the holes have non-zero acceleration. However, the prediction has not yet been demonstrated in observations. Here, we report four electron holes whose acceleration/deceleration is obtained by fitting the spatial separations and detection time delays between different Magnetospheric Multiscale spacecraft. We find that electron hole acceleration/deceleration is related to the ion velocity distribution gradient at the hole's velocity. We observe net velocity changes of ions passing through the accelerating/decelerating holes, in accordance with theoretical predictions. Therefore, we show that electron holes with non-zero acceleration can cause the velocity of passing ions to increase in the acceleration direction.

2.
Micromachines (Basel) ; 14(9)2023 Aug 26.
Article in English | MEDLINE | ID: mdl-37763833

ABSTRACT

The straightness error of guideways is one of the key indicators of an ultra-precision machine, which plays an important role in the machining accuracy of a workpiece. In order to measure the straightness error of a long-distance ultra-precision guideway accurately, a splicing measurement for the straightness error of a guideway using a high-precision flat mirror and displacement sensor was proposed in this paper, and the data splicing processing algorithm based on coordinate transformation was studied. Then, comparative experiments on a splicing measurement and direct measurement of the straightness error were carried out on a hydrostatic guideway grinder. The maximum difference between the two measurements was 0.3 µm, which was far less than the straightness error of 5.8 µm. The experiment demonstrated the correctness of the proposed splicing measurement method and data processing algorithm. To suppress the influence of the straightness error on machining accuracy, a straightness error compensation algorithm based on error rotation transformation and vertical axis position correction was proposed, and the grinding experiment of a plane optics with a size of 1400 mm × 500 mm was carried out. Without error compensation grinding, the flatness error of the element was 7.54 µm. After error compensation grinding, the flatness error was significantly reduced to 2.98 µm, which was less than the straightness errors of the guideways. These results demonstrated that the straightness error of the grinding machine had been well suppressed.

3.
Sensors (Basel) ; 23(15)2023 Jul 27.
Article in English | MEDLINE | ID: mdl-37571524

ABSTRACT

This research aims to analyze the impact of the Earth-Space link on the Automatic Identification System (AIS) signals of ships. To achieve this, we established a simulation system that measures the receiving power of AIS signals via satellite platforms. We validated the system by utilizing observation data from Tiantuo-5. Through this simulation, we quantitatively analyzed the effects of ionospheric TEC (Total Electron Content) and space loss on the received power. During the processing of observation data, we construct a geometric propagation model utilizing the measured positions of both the satellite and the ship. We then calculate the antenna gain and remove any system errors. Additionally, we eliminate the deviation of elevation and azimuth angles caused by satellite motion. This allows us to determine the actual power of different ships reaching the receiving platform. Upon comparing the measured power data with the simulated power, it was noted that both exhibited an increasing trend as the elevation angle increased. This led to an RMSE (Root Mean Square Error) result of approximately one, indicating the accuracy of the simulation system. These findings hold significant implications for analyzing interference factors in satellite-ground links.

4.
Materials (Basel) ; 16(4)2023 Feb 04.
Article in English | MEDLINE | ID: mdl-36836972

ABSTRACT

In this work, hierarchically porous SiC ceramics were prepared via the foaming method. Porous ceramics with tunable, uniform, and bimodal pore structures were successfully fabricated in a facile way. The formation mechanisms of the 1st and 2nd modal macropores are the H2O2 foaming process and SiC particle overlap, respectively. The effect of pore-foaming agent amount, foaming temperature, and surfactant was investigated. According to the results, with increasing H2O2 amount, the porosity, pore size, and interconnectivity of the 1st modal pores increased, whereas bulk density and strength decreased. The porosity increased while the strength decreased as the foaming temperature increased. Surfactants increased pore interconnectivity and porosity. When the foaming temperature was 85 °C, and the addition of H2O2 was 5 wt.%, the porosity, bulk density, flexural strength, and compressive strength were 56.32%, 2.8301 g/cm3, 11.94 MPa, and 24.32 MPa, respectively. Moreover, SiC porous ceramics exhibited excellent corrosion resistance to acids and alkalis.

5.
J Healthc Eng ; 2023: 5816473, 2023.
Article in English | MEDLINE | ID: mdl-36844949

ABSTRACT

Objective: To investigate anatomical and visual outcomes of macular hole (MH) after inverted internal limiting membrane (ILM) flap technique for idiopathic macular hole (IMH). Methods: A total of 13 IMH cases diagnosed in Shanxi Eye Hospital between January 2015 and June 2016 were included in the study. All patients underwent vitrectomy combined with indocyanine green-assisted inverted ILM flap technique. The MH closure rate, best-corrected visual acuity (BCVA), changes of ellipsoid zone (EZ), and external limiting membrane (ELM) were examined before operation and one, three, and six months after operation. Furthermore, 488 nm fundus autofluorescence (FAF) and spectral domain optical coherence tomography (SD-OCT) were used to observe the dynamic changes in function of macular area after surgery. Results: One month after the surgery, the MH closure rate was 100% and the visual acuity (VA) was stable, with no recurrence. Additionally, the average logMAR BCVA before operation was 1.208 ± 0.158, and this value became 0.877 ± 0.105 one month after the operation, showing a significant decrease. Three months after surgery, the average logMAR BCVA was 0.792 ± 0.103, which was significantly lower than the level one month after the surgery but much higher than that six months after surgery (0.708 ± 0.131). Besides, the diameter of the EZ defect of the postoperative one month, three months, and six months was (1377.46 ± 198.65) µm, (964.62 ± 336.26) µm, and (817.08 ± 442.99) µm, respectively. In postoperative one month, three months, and six months, the diameter of the ELM defect diameter was (969.62 ± 189.92) µm, (649.92 ± 413.15) µm, and (557.62 ± 412.50) µm, respectively. The diameter of both EZ and ELM defects was significantly reduced with the passage of time after surgery. Conclusion: Inverted ILM flap technique can reconstruct macular anatomical structure and improve VA. This technique is effective for the treatment of IMH with large MH minimum diameter and base diameter.


Subject(s)
Retinal Perforations , Humans , Retinal Perforations/surgery , Retinal Perforations/diagnosis , Retrospective Studies , Retina/diagnostic imaging , Retina/surgery , Visual Acuity , Surgical Flaps
6.
Nat Commun ; 14(1): 438, 2023 Jan 27.
Article in English | MEDLINE | ID: mdl-36707521

ABSTRACT

Diffuse aurora at the Earth's high latitude regions is mainly caused by the low-energy (0.1-30 keV) electron precipitation which carries the major energy flux into the nightside upper atmosphere. Previous studies have demonstrated that combined scattering by the upper- and lower- band chorus waves acts as the dominant cause of diffuse auroral precipitation, but that is not necessarily the case as these two types of waves do not always occur simultaneously, with the lower-band more often. Here we report that the lower-band chorus satisfying the preferred condition can generate their second harmonics so as to trigger the diffuse auroral electron precipitation. We find that the lower-band chorus alone can only cause the precipitation of electrons greater than 4 keV, while the self-consistently generated second harmonic is weak but still able to result in the electron precipitation below 4 keV. The combined effect of those modes results in the observed pancake electron distributions and the diffuse aurora. Our results clearly demonstrate an alternative but universal mechanism of chorus-driven diffuse aurora in the Earth, which may also apply to the auroral formation in other planetary magnetospheres.

7.
Br J Ophthalmol ; 107(10): 1458-1466, 2023 10.
Article in English | MEDLINE | ID: mdl-35840290

ABSTRACT

OBJECTIVE: This study aimed to investigate the prevalence of glaucoma with associated factors in the rural populations of 10 provinces in China. DESIGN: A population-based cross-sectional study. METHODS: All participants aged 6 years or older from 10 provinces completed visual acuity testing, slit-lamp examination, ophthalmoscopy and non-contact tonometry. Glaucoma suspects underwent fundus photography, Goldmann applanation tonometry, visual field testing and gonioscopy. Glaucoma was determined according to the International Society of Geographical and Epidemiological Ophthalmology classification scheme. Associations of demographics and medical factors with glaucoma were assessed using multiple logistic regression models. RESULTS: From June 2017 to October 2018, 48 398 of 52 041 participants were included in the final analyses. The age-standardised prevalence of glaucoma was 1.7% (95% CI 1.55% to 1.78%) among the participants older than 6 years, which was 2.1% (95% CI 1.93% to 2.23%) in participants aged over 40 years. The constituent ratios of glaucoma were: 44.4% primary angle-closure glaucoma (PACG), 34.7% primary open-angle glaucoma, 2.6% congenital glaucoma and 18.3% other types of glaucoma. Increasing age, smoking, cerebral stroke, type 2 diabetes, higher education (college or more) and higher personal income were significant risk factors for PACG. The unilateral and bilateral blindness rates in the entire study population were 4.692% and 1.068%, respectively. A family history of glaucoma was a significant risk factor for the prevalence of glaucoma and blindness in at least one eye. CONCLUSIONS: Rural populations have a high prevalence of glaucoma, which should be included in chronic disease management programmes in China for long-term care.


Subject(s)
Diabetes Mellitus, Type 2 , Glaucoma, Angle-Closure , Glaucoma, Open-Angle , Humans , Adult , Middle Aged , Intraocular Pressure , Cross-Sectional Studies , Glaucoma, Open-Angle/diagnosis , Rural Population , Glaucoma, Angle-Closure/diagnosis , Glaucoma, Angle-Closure/epidemiology , Age Distribution , Blindness/epidemiology , Gonioscopy , Prevalence , China/epidemiology
8.
Neurologist ; 28(1): 11-18, 2023 Jan 01.
Article in English | MEDLINE | ID: mdl-35452441

ABSTRACT

BACKGROUND: Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive neuromodulation technique. The purpose of our study is to explore the effects of low-frequency (0.5 Hz) and high-frequency (10 Hz) rTMS on neurological function, motor function, and excitability of cortex in Chinese ischemic stroke patients. MATERIALS AND METHODS: A total of 240 ischemic stroke patients were collected. The National Institutes of Health Stroke Scale (NIHSS), modified Rankin Scale (mRS), motor-evoked potential (MEP) cortical latency, central motor conduction time (CMCT), Fugel-Meyer assessment (FMA), Berg balance scale (BBS), and modified Barthel index (MBI) scores were recorded. RESULTS: After treatment, the NIHSS, mRS, MEP cortical latency, CMCT, FMA, BBS, and MBI scores of the high-frequency group and low-frequency group were significantly improved than the sham stimulation group, and the changes in the low-frequency group were more significant (adjusted P <0.05). Compared with the sham stimulation group, high-frequency stimulation reduced the NIHSS score by 9.5%, mRS score by 12.6%, MEP latency by 2.5%, and CMCT by 5.8%, and increased the upper limb FMA scale by 16.4%, lower limb FMA scale by 8.8%, BBS by 26.3%, and MBI by 9.3%, while low-frequency stimulation reduced the NIHSS score by 23.8%, mRS score by 25.3%, MEP Latency by 11.7%, and CMCT by 9.1%, and increased the upper limb FMA scale by 24.1%, lower limb FMA scale by 18.4%, BBS by 27.4%, and MBI by 23.7% in our cohort. CONCLUSIONS: Low-frequency rTMS is better than high-frequency rTMS stimulation in improving neurological function, motor function, and excitability of cortex in ischemic stroke.


Subject(s)
Ischemic Stroke , Motor Cortex , Stroke Rehabilitation , Stroke , Humans , Stroke/therapy , Stroke Rehabilitation/methods , Transcranial Magnetic Stimulation/methods , Treatment Outcome
9.
Comput Math Methods Med ; 2022: 2185908, 2022.
Article in English | MEDLINE | ID: mdl-35401775

ABSTRACT

Volleyball is a sport of teamwork competition and tactical coordination. It tests the ability of team members to cooperate with each other and personal resilience. With the development of wireless communication networks, how to use wireless communication networks in the analysis of volleyball tactics is the subject of this article. To explore how to design the volleyball tactics analysis model of the wireless communication network, this paper proposes the method of LTE system and MIMO technology and designs the tactics analysis model based on the characteristics of the wireless network, then combined volleyball tactics and game theory to design a wireless communication network volleyball tactics analysis model. Then, this paper designs the simulation experiment of scene allocation problem, the algorithm simulation experiment, and the comparative investigation and analysis of volleyball game spiking technical ability. The results of the experiment are optimized for the tactical analysis model, and finally, the improvement of the training of the volleyball tactical analysis model based on the wireless communication network is verified through comparative experiments. The experimental results show that the team fit of the volleyball tactical analysis model training based on the wireless communication network has increased by 22.12% compared with the traditional volleyball tactical training. Compared with the traditional volleyball tactical training, the personal on-the-spot adaptability of the volleyball tactical analysis model training based on the wireless communication network has increased by 9.05%.


Subject(s)
Game Theory , Models, Biological , Volleyball , Wireless Technology , Algorithms , Humans
10.
Urol Oncol ; 40(6): 223-228, 2022 06.
Article in English | MEDLINE | ID: mdl-32482510

ABSTRACT

Due to its rarity and lack of prospective studies, clinical evidence for the management of the inguinal lymphatic nodal basin with radiation therapy in penile cancer (PeCa) has been limited. In this report, we review the current literature and further investigated the landscape of radiation sensitivity in nodal metastases of PeCa utilizing our well-established genome-based radiosensitivity index (RSI) platform. We hypothesized that optimal therapeutic gain could be achieved in PeCa stratified by the combination of clinicopathological parameters, genomic heterogeneity, and RSI-based radiation dose prescription (RxRSI). Similar to primary PeCa lesions, we found that the majority of PeCa nodal metastases are genomically radioresistant with significant heterogeneity. RxRSI should be considered to inform and optimize the radiation therapy dose prescription to the individual tumor biology.


Subject(s)
Penile Neoplasms , Genomics , Humans , Lymph Node Excision , Male , Penile Neoplasms/pathology
11.
Transl Oncol ; 14(10): 101165, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34246048

ABSTRACT

BACKGROUND: Soft-tissue sarcomas (STS) are heterogeneous with variable response to radiation therapy (RT). Utilizing the radiosensitivity index (RSI) we estimated the radiobiologic ratio of lethal to sublethal damage (α/ß), genomic-adjusted radiation dose(GARD), and in-turn a biological effective radiation dose (BED). METHODS: Two independent cohorts of patients with soft-tissue sarcoma were identified. The first cohort included 217 genomically-profiled samples from our institutional prospective tissue collection protocol; RSI was calculated for these samples, which were then used to dichotomize the population as either highly radioresistant (HRR) or conventionally radioresistant (CRR). In addition, RSI was used to calculate α/ß ratio and GARD, providing ideal dosing based on sarcoma genomic radiosensitivity. A second cohort comprising 399 non-metastatic-STS patients treated with neoadjuvant RT and surgery was used to validate our findings. RESULTS: Based on the RSI of the sample cohort, 84% would historically be considered radioresistant. We identified a HRR subset that had a significant difference in the RSI, and clinically a lower tumor response to radiation (2.4% vs. 19.4%), 5-year locoregional-control (76.5% vs. 90.8%), and lower estimated α/ß (3.29 vs. 5.98), when compared to CRR sarcoma. Using GARD, the dose required to optimize outcome in the HRR subset is a BEDα/ß=3.29 of 97 Gy. CONCLUSIONS: We demonstrate that on a genomic scale, that although STS is radioresistant overall, they are heterogeneous in terms of radiosensitivity. We validated this clinically and estimated an α/ß ratio and dosing that would optimize outcome, personalizing dose.

12.
Rep Pract Oncol Radiother ; 26(1): 29-34, 2021.
Article in English | MEDLINE | ID: mdl-33948299

ABSTRACT

BACKGROUND: The purpose of this study was to characterize pre-treatment non-contrast computed tomography (CT) and 18F-fluorodeoxyglucose positron emission tomography (PET) based radiomics signatures predictive of pathological response and clinical outcomes in rectal cancer patients treated with neoadjuvant chemoradiotherapy (NACR T). MATERIALS AND METHODS: An exploratory analysis was performed using pre-treatment non-contrast CT and PET imaging dataset. The association of tumor regression grade (TRG) and neoadjuvant rectal (NAR) score with pre-treatment CT and PET features was assessed using machine learning algorithms. Three separate predictive models were built for composite features from CT + PET. RESULTS: The patterns of pathological response were TRG 0 (n = 13; 19.7%), 1 (n = 34; 51.5%), 2 (n = 16; 24.2%), and 3 (n = 3; 4.5%). There were 20 (30.3%) patients with low, 22 (33.3%) with intermediate and 24 (36.4%) with high NAR scores. Three separate predictive models were built for composite features from CT + PET and analyzed separately for clinical endpoints. Composite features with α = 0.2 resulted in the best predictive power using logistic regression. For pathological response prediction, the signature resulted in 88.1% accuracy in predicting TRG 0 vs. TRG 1-3; 91% accuracy in predicting TRG 0-1 vs. TRG 2-3. For the surrogate of DFS and OS, it resulted in 67.7% accuracy in predicting low vs. intermediate vs. high NAR scores. CONCLUSION: The pre-treatment composite radiomics signatures were highly predictive of pathological response in rectal cancer treated with NACR T. A larger cohort is warranted for further validation.

13.
Exp Ther Med ; 21(4): 332, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33732305

ABSTRACT

The present study aimed to investigate the mechanisms of anti-VEGF treatment prior to eye surgery to reduce intraoperative bleeding. A total of 30 patients with proliferative vitreoretinopathy after clinical diagnosis were enrolled in the present study as the surgical group. Furthermore, 30 patients underwent intravitreal injection of the anti-VEGF drug conbercept and were considered the drug pretreatment group. The aqueous and vitreous humors from the eyes of patients in the surgical group were drawn during pars plana vitrectomy surgery. The aqueous humor in the eyes of patients in the drug pretreatment group was drawn prior to conbercept treatment and seven days after conbercept treatment immediately prior to surgery. The vitreous humor in this group was only taken during surgery. Furthermore, ELISA was used to detect the levels of VEGF-A and -B in the aqueous and vitreous humors. Semi-quantitative determination of VEGF-A and VEGF-B levels in fibrovascular proliferative membranes was performed using immunohistochemical staining. The results indicated that in the drug group, the levels of VEGF-A in the aqueous humor of patients prior to and after conbercept injection were 197.66±48.00 and 3.39±2.54 pg/ml, respectively. The levels of VEGF-A in the vitreous humor of patients in the surgical and drug groups were 267.53±179.60 and 21.43±5.81 pg/ml after injection, respectively. The levels of VEGF-B in the aqueous humor of patients prior to and after conbercept injection were 13.66±3.30 (before injection) and 2.17±0.94 pg/ml (after injection), respectively. The levels of VEGF-B in the vitreous humor of patients in the surgical and drug groups were 127.36±16.72 and 18.56±9.82 pg/ml after injection, respectively (P<0.05). Furthermore, in the drug group, the surgery time, bleeding and capillary formation were significantly reduced compared with those in the surgical group. Taken together, these results suggested that the levels of VEGF-A and -B decreased significantly in the aqueous humor of patients with PDR after conbercept injection. Furthermore, the levels of VEGF-A and -B in the vitreous humor of patients dropped significantly in the drug group compared with those in the surgical group. These results provide theoretical clinical support for the preoperative application of conbercept for patients with PDR.

14.
Iran J Public Health ; 50(10): 2010-2016, 2021 Oct.
Article in English | MEDLINE | ID: mdl-35223568

ABSTRACT

BACKGROUND: To investigate the relationship between different dietary patterns and the levels of bone mineral density (BMD) in middle-aged and aged people, and to provide references for the nutritional prevention of osteoporosis. METHODS: A total of 476 residents aged 45 yr or more in Qiqihar City were enrolled from Aug 2018 to Feb 2019. They took a Food Frequency Questionnaire for dietary survey. Their dietary patterns were analyzed using the factor analysis method, and BMD were detected using ultrasound bone densitometer, to explore the relationship between different dietary patterns and BMD levels. RESULTS: Four dietary patterns were obtained in the survey: relatively balanced, oil-salt, milk-tuber, and aquatic. Among them, the prevalence of osteoporosis reached 21.8%. High-level relatively balanced dietary pattern (OR=0.588, 95%CI= 0.363-0.951) and high-level dairy-potato food dietary pattern (OR=0.668, 95%CI= 0.370-0.983) were associated with lower risk of osteoporosis. CONCLUSION: A balanced diet and a high intake of dairy-potato food dietary pattern were associated with a lower prevalence of osteoporosis. It is recommended that middle-aged and aged people should have a balanced diet with more dairy products and potatoes to protect bone health.

15.
Prostate Cancer Prostatic Dis ; 24(1): 140-149, 2021 03.
Article in English | MEDLINE | ID: mdl-32651467

ABSTRACT

BACKGROUND: To determine whether combining brachytherapy with immunotherapy is safe in prostate cancer (PCa) and provides synergistic effects, we performed a Phase I/II trial on the feasibility, safety, and benefit of concurrent delivery of anti-PD-1 (nivolumab) with high-dose-rate (HDR) brachytherapy and androgen deprivation therapy (ADT) in patients with Grade Group 5 (GG5) PCa. METHODS: Eligible patients were aged 18 years or older with diagnosis of GG5 PCa. Patients received ADT, nivolumab every two weeks for four cycles, with two cycles prior to first HDR, and two more cycles prior to second HDR, followed by external beam radiotherapy. The primary endpoint was to determine safety and feasibility. This Phase I/II trial is registered with ClinicalTrials.gov (NCT03543189). RESULTS: Between September 2018 and June 2019, six patients were enrolled for the Phase I safety lead-in with a minimum observation period of 3 months after nivolumab administration. Overall, nivolumab was well tolerated in combination with ADT and HDR treatment. One patient experienced a grade 3 dose-limiting toxicity (elevated Alanine aminotransferase and Aspartate aminotransferase) after the second cycle of nivolumab. Three patients (50%) demonstrated early response with no residual tumor detected in ≥4 of 6 cores on biopsy post-nivolumab (4 cycles) and 1-month post-HDR. Increase in CD8+ and FOXP3+/CD4+ T cells in tissues, and CD4+ effector T cells in peripheral blood were observed in early responders. CONCLUSION: Combination of nivolumab with ADT and HDR is well tolerated and associated with evidence of increased immune infiltration and antitumor activity.


Subject(s)
Brachytherapy/methods , Neoplasm Grading , Nivolumab/administration & dosage , Prostatic Neoplasms/therapy , Aged , Antineoplastic Agents, Immunological/administration & dosage , Dose Fractionation, Radiation , Feasibility Studies , Follow-Up Studies , Humans , Male , Prostatic Neoplasms/pathology , Retrospective Studies , Treatment Outcome
16.
J Med Imaging Radiat Oncol ; 65(1): 102-111, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33258556

ABSTRACT

INTRODUCTION: To develop a radiomic-based model to predict pathological complete response (pCR) and outcome following neoadjuvant chemoradiotherapy (NACRT) in oesophageal cancer. METHODS: We analysed 68 patients with oesophageal cancer treated with NACRT followed by esophagectomy, who had staging 18F-fluorodeoxyglucose (18 F-FDG) positron emission tomography (PET) and computed tomography (CT) scans performed at our institution. An in-house data-chjmirocterization algorithm was used to extract 3D-radiomic features from the segmented primary disease. Prediction models were constructed and internally validated. Composite feature, Fc  = α * FPET  + (1 - α) * FCT , 0 ≤ α ≤ 1, was constructed for each corresponding CT and PET feature. Loco-regional control (LRC), recurrence-free survival (RFS), metastasis-free survival (MFS) and overall survival (OS) were estimated by Kaplan-Meier analysis, and compared using log-rank test. RESULTS: Median follow-up was 59 months. pCR was achieved in 34 (50%) patients. Five-year RFS, LRC, MFS and OS were 67.1%, 88.5%, 75.6% and 57.6%, respectively. Tumour Regression Grade (TRG) 0-1 indicative of complete response or minimal residual disease was significantly associated with improved 5-year LRC [93.7% vs 71.8%; P = 0.020; HR 0.19, 95% CI 0.04-0.85]. Four sepjmirote pCR predictive models were built for CT alone, PET alone, CT+PET and composite. CT, PET and CT+PET models had AUC 0.73 ± 0.08, 0.66 ± 0.08 and 0.77 ± 0.07, respectively. The composite model resulted in an improvement of pCR predicting power with AUC 0.87 ± 0.06. Stratifying patients with a low versus high radiomic score showed clinically relevant improvement in 5-year LRC favouring low-score group (91.1% vs. 80%, 95% CI 0.09-1.77, P = 0.2). CONCLUSION: The composite CT/PET radiomics model was highly predictive of pCR following NACRT. Validation in larger data sets is warranted to determine whether the model can predict clinical outcomes.


Subject(s)
Esophageal Neoplasms , Neoadjuvant Therapy , Chemoradiotherapy , Esophageal Neoplasms/diagnostic imaging , Esophageal Neoplasms/therapy , Fluorodeoxyglucose F18 , Humans , Positron Emission Tomography Computed Tomography , Radiopharmaceuticals , Retrospective Studies
17.
JCO Glob Oncol ; 6: 1510-1518, 2020 10.
Article in English | MEDLINE | ID: mdl-33021855

ABSTRACT

PURPOSE: Cervical cancer remains a major health challenge in low- to middle-income countries. We present the experiences of two centers practicing in variable resource environments to determine predictors of improved radiochemotherapy treatment. METHODS AND MATERIALS: This comparative review describes cervical cancer presentation and treatment with concurrent chemoradiotherapy with high-dose-rate brachytherapy between 2014 and 2017 at the National Radiotherapy Oncology and Nuclear Medicine Center (NRONMC) in Korle-Bu Teaching Hospital, Accra, Ghana, and Moffitt Cancer Center (MCC), Tampa, FL. RESULTS: Median follow-up for this study was 16.9 months. NRONMC patients presented with predominantly stage III disease (42% v 16%; P = .002). MCC patients received para-aortic node irradiation (16%) and interstitial brachytherapy implants (19%). Median treatment duration was longer for NRONMC patients compared with MCC patients (59 v 52 days; P < .0001), and treatment duration ≥ 55 days predicted worse survival on multivariable analysis (MVA; P = .02). Stage ≥ III disease predicted poorer local control on MVA. There was a difference in local control among patients with stage III disease (58% v 91%; P = .03) but not in survival between MCC and NRONMC. No significant difference in local control was observed for stage IB, IIA, and IIB disease. CONCLUSION: Although there were significant differences in disease presentation between the two centers, treatment outcomes were similar for patients with early-stage disease. Longer treatment duration and stage ≥ III disease predicted poor outcomes.


Subject(s)
Brachytherapy , Carcinoma, Squamous Cell , Uterine Cervical Neoplasms , Carcinoma, Squamous Cell/drug therapy , Chemoradiotherapy , Female , Ghana , Humans , Uterine Cervical Neoplasms/drug therapy , Uterine Cervical Neoplasms/radiotherapy
18.
Future Oncol ; 16(30): 2411-2420, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32686956

ABSTRACT

Aim: Genomic-based risk stratification to personalize radiation dose in rectal cancer. Patients & methods: We modeled genomic-based radiation dose response using the previously validated radiosensitivity index (RSI) and the clinically actionable genomic-adjusted radiation dose. Results: RSI of rectal cancer ranged from 0.19 to 0.81 in a bimodal distribution. A pathologic complete response rate of 21% was achieved in tumors with an RSI <0.31 at a minimal genomic-adjusted radiation dose of 29.76 when modeling RxRSI to the commonly prescribed physical dose of 50 Gy. RxRSI-based dose escalation to 55 Gy in tumors with an RSI of 0.31-0.34 could increase pathologic complete response by 10%. Conclusion: This study provides a theoretical platform for development of an RxRSI-based prospective trial in rectal cancer.


Subject(s)
Genomics , Precision Medicine , Radiotherapy Dosage , Rectal Neoplasms/genetics , Rectal Neoplasms/radiotherapy , Adult , Aged , Aged, 80 and over , Combined Modality Therapy/methods , Dose-Response Relationship, Radiation , Female , Gene Expression Profiling , Genomics/methods , Humans , Male , Middle Aged , Neoplasm Grading , Neoplasm Metastasis , Neoplasm Staging , Odds Ratio , Precision Medicine/methods , Radiation Tolerance/genetics , Rectal Neoplasms/diagnosis , Rectal Neoplasms/mortality , Transcriptome , Treatment Outcome
19.
J Environ Pathol Toxicol Oncol ; 39(1): 89-99, 2020.
Article in English | MEDLINE | ID: mdl-32479015

ABSTRACT

Oxidative stress and inflammation are regarded as prime reasons for the progression and development of diabetic retinopathy. Currently, nuclear factor erythroid-2-related factor 2 (Nrf2), thioredoxin interacting protein (TXNIP) and NLRP3 inflammasome pathways are under increasing focus in research on oxidative stress and inflammation-related diseases. On the other hand, tilianin (TN) has received much attention because of its various pharmacological properties. Based on results of these studies, this investigation was performed to inspect the therapeutic efficiency of TN on the retina in diabetic rats. Rats were arbitrarily assigned to three groups: control group, diabetic group, and diabetic plus TN (20 mg/ kg body weight for 42 days, orally) group. TN supplementation in diabetic rats, their food intake, fasting blood glucose status, glycosylated hemoglobin (HbA1c) levels were drastically reduced, and there was a marked augmentation in serum insulin status. TN treatment of diabetic rats increased mRNA expression of Nrf2 and its target gene, HO-1, and noticeably decreased the malondialdehyde status. Activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidases (GPX) were increased relative to diabetic rats. Furthermore, administering TN to the diabetic rats resulted in decreased expression of TXNIP, NOD-like receptor protein 3 (NLRP3), apoptosis-associated speck-like protein containing a CARD (ASC), caspase-1, and IL-1ß proteins and decreased distribution of TXNIP, NLRP3, ASC, and caspase-1 proteins in retinas. In addition, TN treatment ameliorated morphological and morphometric changes in the retinas of diabetic rats. Together, all of these findings provide clear evidence that TN treatment of diabetic rats attenuated diabetic retinal changes through its hypoglycemic, antioxidant, and anti-inflammatory properties. The antioxidant and anti-inflammatory effects in diabetic retinas occur at least in part through the modulation of Nrf2/TXNIP/NLRP3 inflammasome pathways, which may have remedial benefits in the healing of diabetic retinopathy.


Subject(s)
Diabetes Mellitus, Experimental/drug therapy , Flavonoids/pharmacology , Glycosides/pharmacology , Inflammasomes/drug effects , Protective Agents/pharmacology , Retina/drug effects , Signal Transduction/drug effects , Animal Feed/analysis , Animals , Diet , Dietary Supplements/analysis , Male , Random Allocation , Rats , Rats, Wistar , Retina/pathology
20.
J Med Imaging Radiat Oncol ; 64(3): 444-449, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32386109

ABSTRACT

INTRODUCTION: Innovative biomarkers to predict treatment response in rectal cancer would be helpful in optimizing personalized treatment approaches. In this study, we aimed to develop and validate a CT-based radiomic imaging biomarker to predict pathological response. METHODS: We used two independent cohorts of rectal cancer patients to develop and validate a CT-based radiomic imaging biomarker predictive of treatment response. A total of 91 rectal cancer cases treated from 2009 to 2018 were assessed for the tumour regression grade (TRG) (0 = pathological complete response, pCR; 1 = moderate response; 2 = partial response; 3 = poor response). Exploratory analysis was performed by combining pre-treatment non-contrast CT images and patterns of TRG. The models built from the training cohort were further assessed using the independent validation cohort. RESULTS: The patterns of pathological response in training and validation groups were TRG 0 (n = 14, 23.3%; n = 6, 19.4%), 1 (n = 31, 51.7%; n = 15, 48.4%), 2 (n = 12, 20.0%; n = 7, 22.6%) and 3 (n = 3, 5.0%; n = 3, 9.7%), respectively. Separate predictive models were built and analysed from CT features for pathological response. For pathological response prediction, the model including 8 radiomic features by random forest method resulted in 83.9% accuracy in predicting TRG 0 vs TRG 1-3 in validation. CONCLUSION: The pre-treatment CT-based radiomic signatures were developed and validated in two independent cohorts. This imaging biomarker provided a promising way to predict pCR and select patients for non-operative management.


Subject(s)
Machine Learning , Rectal Neoplasms/diagnostic imaging , Rectal Neoplasms/therapy , Tomography, X-Ray Computed , Adult , Aged , Aged, 80 and over , Biomarkers, Tumor/analysis , Chemoradiotherapy , Female , Florida , Humans , Male , Middle Aged , Neoadjuvant Therapy , Neoplasm Grading , Neoplasm Staging , Predictive Value of Tests , Rectal Neoplasms/pathology , Retrospective Studies
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