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1.
Ann Plast Surg ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38984745

RESUMO

BACKGROUND: Abdominal wall reconstruction (AWR) is a treatment option for structural defects of the abdominal wall. The most frequently cited publications related to AWR have not been quantitatively or qualitatively assessed. This bibliometric analysis characterizes and assesses the most frequently cited AWR publications, to identify trends, gaps, and guide future efforts for the international research community. METHODS: The 100 most cited publications in AWR were identified on Web of Science, across all available journal years (from May 1964 to December 2023). Study details, including the citation count, main content focus, and outcome measures, were extracted and tabulated from each publication. Oxford Centre for Evidence-Based Medicine levels of evidence (LOE) of each study were also assessed. RESULTS: The 100 most cited publications in AWR were cited by a total of 9674 publications. Citations per publication ranged from 43 to 414 (mean 96.7 ± 52.48). Most publications were LOE 3 (n = 60), representative of the large number of retrospective cohort studies. The number of publications for LOE 5, 4, 3, 2, and 1 was 21, 2, 60, 2, and 12, respectively. The main content focus was surgical technique in 44 publications followed by outcomes in 38 publications. Patient-reported outcome measures were used in 3 publications, and no publications reported validated esthetic outcome measures. CONCLUSIONS: Overall, 3 was the LOE for most frequently cited AWR publications, with more publications below LOE 3 than above LOE 3. Validated outcome measures and patient-reported outcome measures were infrequently incorporated in the studies evaluated.

2.
Pract Radiat Oncol ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38888539

RESUMO

PURPOSE: The schedule of cisplatin concurrent with definitive radiation for squamous carcinoma of the head and neck remains controversial. Most institutions deliver either a high-dose "bolus" schedule once every 3 weeks or a low-dose weekly schedule. We compared these 2 schedules via a simplified network meta-analysis with a common comparator. METHODS AND MATERIALS: We performed a PRISMA-concordant systematic review to identify randomized controlled trials comparing cisplatin with cetuximab for nonmetastatic, locoregionally advanced squamous carcinoma of the head and neck treated with definitive radiation. Trials incorporating primary surgery or induction therapy were excluded. Patient survival times were extracted on a per-event basis from the published curves using a digitizer and validated against published point estimates and hazard ratios (HRs). Survival was compared using random effects Cox regression under a frequentist framework. Toxicity and secondary endpoints were analyzed qualitatively. The Cochrane method assessed the risk of bias. The analysis plan was preregistered with the Open Science Foundation. RESULTS: Five randomized trials were identified, including 1678 patients. There was no statistical difference in overall survival between weekly and bolus regimens (HR, 0.90; 95% CI, 0.53-1.52, P = .345). This Cox model suggested that for the average patient in the cohort, the absolute difference in 5-year overall survival between weekly and bolus regimens was +1.2% (95% CI, -6.1%-+5.9%, P = .345). Secondary endpoints and toxicity were not obviously different by regimen, qualitatively. CONCLUSIONS: The cetuximab trials provide indirect data suggesting that the differences between cisplatin schedules are subtle.

3.
Heliyon ; 10(11): e31937, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38868043

RESUMO

This study aims to pharmacologically validate Haridra Khanda (HK) and Manjishthadi Kwatham (brihat) (MMK) in allergy management using invivo and invitro studies to rationalize the prescription of these two ayurvedic polyherbal drug formulations, which are currently used in Indian government hospitals. Experimental animals received HK and MMK orally from day 0 to day 14 and histamine (1 mg/kg b.w/i.v) and 1 % evans blue (EB) (0.1 mL) via tail vein on day 14. The compound 48/80 (intracutaneous) challenged mice model followed the same technique. The former mimicked acute anaphylaxis and the latter mast cell degranulation. For both models, EB dye leakage was quantified spectrophotometrically to determine vascular permeability. Plasma histamine was measured in Compound 48/80-induced animals using LC-ESI-MS/MS. The guineapig received HK and MMK p.o. and 0.6 % histamine sprayed in a histamine chamber to simulate allergic rhinitis. Blood eosinophil count and sneeze rate were measured in histamine-challenged guineapigs. Goat R.B.C. membrane stability assay (mammalian cell membrane toxicity) and intracellular histamine-induced cytosolic Ca2+ release assay in Chinese hamster ovary (CHO) cells were performed in vitro. For both histamine and Compound 48/80 challenged animals, HK (22.81 % and 14.58 %) and MMK (19.71 % and 22.40 %) significantly reduced EB dye leakage (p < 0.05). Both formulations, HK and MMK considerably (p < 0.05) decreased plasma histamine (29.62 % and 25.37 % respectively) in mice and eosinophilic count (11.56 % and 9.94 % respectively) and sneeze rate (42.58 % and 29.03 % respectively) in guinea pigs. In membrane stability experiment, HK and MMK reduced RBC lysis. Both HK and MMK raw/dialysate blocked CHO cell cytosolic Ca2+ release. HK and MMK activities mimic mast cell stabilization with possible H1 receptor inactivation seen by decreased Ca2+ efflux and thus indicate potential for allergic rhinitis management. The combination of activities is usually related with curative and prophylactic therapy and might lead future clinical trials and therapies.

4.
Inorg Chem ; 63(8): 3781-3794, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38346445

RESUMO

Materials with an extreme lattice thermal conductivity (κl) are indispensable for thermal energy management applications. Layered materials provide an avenue for designing such functional materials due to their intrinsic bonding heterogeneity. Therefore, a microscopic understanding of the crystal structure, bonding, anharmonic lattice dynamics, and phonon transport properties is critically important for layered materials. Alkaline-earth halofluorides exhibit anisotropy from their layered crystal structure, which is strongly determined by axial bond(s), and it is attributed to the large axial ratio (c/a > 2) for CaBrF, CaIF, and SrIF, in which Br/I acts as a rattler, as evidenced from potential energy curves and phonon density of states. The low axial (c/a) ratio leads to relatively isotropic κl values in the BaXF (X = Cl, Br, I) series. MXF (M = Ca, Sr, Ba) compounds exhibit highly anisotropic (a large phonon transport anisotropy ratio of 10.95 for CaIF) to isotropic (a small phonon transport anisotropy ratio of 1.49 for BaBrF) κl values despite their iso-structure. Moreover, ultralow κl (<1 W/m K) values have been predicted for CaBrF, CaIF, and SrIF in the out-of-plane direction due to weak van der Waals (vdWs) bonding. Overall, this comprehensive study on MXF compounds provides insights into designing low κl layered materials with a large axial ratio by fine-tuning out-of-plane bonding from ionic to vdWs bonding.

5.
Pathol Res Pract ; 253: 155032, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38176306

RESUMO

In the spectrum of breast neoplasms, approximately 15 to 20% of all diagnosed cases are triple-negative breast carcinoma. TNBC grows and spreads faster than other invasive breast cancers and has a worse prognosis. The existing therapies and chemotherapeutic drugs have several limitations, so the development of safe and affordable treatment options is currently in demand. Hence, this research focuses on scientifically evaluating the therapeutic anticancer effect of ethyl acetate extract of MSG and its combined efficacy with doxorubicin against TNBC. MSG has shown an IC50 value of 48.40 ± 1.68 µg/ml on the MDA-MB-231 cell line, and the combination of MSG with Dox demonstrated the synergistic effect. Apoptotic changes such as membrane blebbing chromatin condensation were observed in MSG alone and in combination with doxorubicin treatments. Apoptosis was confirmed with Annexin V-FITC/PI staining and increased apoptotic markers such as Cleaved caspase-3 Bax and decreased anti-apoptotic markers Bcl-2 by western blotting. The tumor burden significantly decreased in MSG and combination treatment groups while restoring their body weights. Meanwhile, the Dox-treated group indicated a decreased tumor burden combined with weight loss. The present investigation revealed that MSG and doxorubicin have a synergistic anticancer effect in TNBC.


Assuntos
Acetatos , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Apoptose
6.
Behav Med ; : 1-13, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38193280

RESUMO

The dietary behaviors of Asian American (AA) young adults, who face a growing non-communicable disease burden, are impacted by complex socio-ecological forces. Family plays a crucial role in the lifestyle behaviors of AA young adults; however, little is known on the methods, contributors, and impact of familial dietary influence. This study aims to deconstruct the mechanisms of AA young adult familial dietary influence through a multi-perspective qualitative assessment. A five-phase method of dyadic analysis adapted from past research was employed to extract nuanced insights from dyadic interviews with AA young adults and family members, and ground findings in behavioral theory (the Social Cognitive Theory, SCT). 37 interviews were conducted: 18 young adults, comprising 10 different AA ethnic subgroups, and 19 family members (10 parents, 9 siblings). Participants described dietary influences that were both active (facilitating, shaping, and restricting) and passive (e.g., sharing foods or environment, mirroring food behaviors). Influences connected strongly with multiple SCT constructs (e.g., behavioral capacity, reinforcements for active influences, and expectations, observational learning for passive influences). Familial influence contributed to changes in the total amount, variety, and healthfulness of foods consumed. Intra-family dynamics were crucial; family members often leveraged each other's persuasiveness or food skills to collaboratively influence diet. AA family-based interventions should consider incorporating both passive and active forms of dietary influence within a family unit, involve multiple family members, and allow for individualization to the unique dynamics and dietary behaviors within each family unit.

7.
Int J Radiat Oncol Biol Phys ; 118(3): 650-661, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37717787

RESUMO

PURPOSE: Preoperative stereotactic radiosurgery (SRS) is a feasible alternative to postoperative SRS for resected brain metastases (BM). Most reported studies of preoperative SRS used single-fraction SRS (SF-SRS). The goal of this study was to compare outcomes and toxicity of preoperative SF-SRS with multifraction (3-5 fractions) SRS (MF-SRS) in a large international multicenter cohort (Preoperative Radiosurgery for Brain Metastases-PROPS-BM). METHODS AND MATERIALS: Patients with BM from solid cancers, of which at least 1 lesion was treated with preoperative SRS followed by planned resection, were included from 8 institutions. SRS to synchronous intact BM was allowed. Exclusion criteria included prior or planned whole brain radiation therapy. Intracranial outcomes were estimated using cumulative incidence with competing risk of death. Propensity score matched (PSM) analyses were performed. RESULTS: The study cohort included 404 patients with 416 resected index lesions, of which SF-SRS and MF-SRS were used for 317 (78.5%) and 87 patients (21.5%), respectively. Median dose was 15 Gy in 1 fraction for SF-SRS and 24 Gy in 3 fractions for MF-SRS. Univariable analysis demonstrated that SF-SRS was associated with higher cavity local recurrence (LR) compared with MF-SRS (2-year: 16.3% vs 2.9%; P = .004), which was also demonstrated in multivariable analysis. PSM yielded 81 matched pairs (n = 162). PSM analysis also demonstrated significantly higher rate of cavity LR with SF-SRS (2-year: 19.8% vs 3.3%; P = .003). There was no difference in adverse radiation effect, meningeal disease, or overall survival between cohorts in either analysis. CONCLUSIONS: Preoperative MF-SRS was associated with significantly reduced risk of cavity LR in both the unmatched and PSM analyses. There was no difference in adverse radiation effect, meningeal disease, or overall survival based on fractionation. MF-SRS may be a preferred option for neoadjuvant radiation therapy of resected BMs. Additional confirmatory studies are needed. A phase 3 randomized trial of single-fraction preoperative versus postoperative SRS (NRG-BN012) is ongoing (NCT05438212).


Assuntos
Neoplasias Encefálicas , Lesões por Radiação , Radiocirurgia , Humanos , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirurgia , Neoplasias Encefálicas/patologia , Estudos de Coortes , Fracionamento da Dose de Radiação , Lesões por Radiação/etiologia , Radiocirurgia/efeitos adversos , Radiocirurgia/métodos , Estudos Retrospectivos , Resultado do Tratamento , Ensaios Clínicos Fase III como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
Clin Case Rep ; 11(10): e8005, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37786459

RESUMO

Key Clinical Message: Understanding the circumstances, leading to unmasking of hidden Brugada syndrome is essential for the practicing clinician and the patients so that they are informed adequately to seek prompt medical attention. Abstract: Brugada syndrome is a genetic arrhythmia syndrome characterized by a coved type of ST-segment elevation in the ECG. The patients are usually asymptomatic, with unmasking of the disease under certain conditions. We are reporting the case of a patient diagnosed with Brugada syndrome, which was unmasked during an attack of dengue fever.

9.
Pract Radiat Oncol ; 13(6): 531-539, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37406774

RESUMO

PURPOSE: Stereotactic body radiation therapy (SBRT) has been used with high effectiveness in early-stage non-small cell lung cancer (NSCLC) but has not been studied extensively in locally advanced NSCLC. We conducted a phase 2 study delivering SBRT to the primary tumor followed by conventionally fractionated chemoradiation to the involved lymph nodes for patients with node-positive locally advanced NSCLC. This manuscript serves as both a guide to planning techniques used on this trial and the subsequent phase 3 study, NRG Oncology LU-008, and to report patient dosimetry and toxicity results. METHODS AND MATERIALS: We initiated a phase 2 multicenter single arm study evaluating SBRT to the primary tumor (50-54 Gy in 3-5 fractions) followed by conventionally fractionated chemoradiation to 60 Gy in 2 Gy fractions with doublet chemotherapy to the involved lymph nodes for patients with stage III or unresectable stage II NSCLC. Patients eligible for adjuvant immunotherapy received up to 12 months of durvalumab. We report a detailed guide for the entire treatment process from computed tomography simulation through treatment planning and delivery. The dosimetric outcomes from the 60 patients who completed therapy on study are reported both for target coverage and normal structure doses. We also report correlation between radiation-related toxicities and dosimetric parameters. RESULTS: Sixty patients were enrolled between 2017 and 2022. Planning techniques used were primarily volumetric modulated arc therapy for SBRT to the primary tumor and conventionally fractionated radiation to the involved nodes, with a minority of cases using dynamic conformal arc technique or static dynamic multileaf collimator intensity modulated radiation therapy. Grade 2 or higher pneumonitis was associated with lung dose V5 Gy > 70% and grade 2 or higher pulmonary toxicity was associated with lung dose V10 Gy > 50%. Only 3 patients (5%) experienced grade 3 or higher pneumonitis. Grade 2 or higher esophagitis was associated with esophageal doses, including mean dose > 20 Gy, V60 Gy > 7%, and D1cc > 55 Gy. Only 1 patient (1.7%) experienced grade 3 esophagitis. CONCLUSIONS: SBRT to the primary tumor followed by conventionally fractionated chemoradiation to the involved lymph nodes is feasible with planning techniques as described. Radiation-related toxicity on this phase 2 study was low. This manuscript serves as a guideline for the recently activated NRG Oncology LU-008 phase 3 trial evaluating this experimental regimen.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Esofagite , Neoplasias Pulmonares , Pneumonia , Lesões por Radiação , Radiocirurgia , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Radiocirurgia/efeitos adversos , Radiocirurgia/métodos , Dosagem Radioterapêutica , Lesões por Radiação/etiologia , Pneumonia/etiologia , Esofagite/etiologia
10.
J Environ Pathol Toxicol Oncol ; 42(4): 15-29, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37522565

RESUMO

According to the World Health Organization (WHO), cancer is the second-highest cause of mortality worldwide, killing nearly 9.6 million people annually. Despite the advances in diagnosis and treatment during the last couple of decades, it remains a serious concern due to the limitations of currently available cancer management strategies. Therefore, alternative strategies are highly required to overcome these glitches. In addition, many etiological factors such as environmental and genetic factors initiate the activation of the Janus kinase (JAK)-signal transducer and activator of the transcription (STAT) pathway. This aberrant activation of the JAK-STAT pathway has been reported in various disease states, including inflammatory conditions, hematologic malignancies, and cancer. For instance, many patients with myeloproliferative neoplasms carry the acquired gain-of-function JAK2 V617F somatic mutation. This knowledge has dramatically improved our understanding of pathogenesis and has facilitated the development of therapeutics capable of suppressing the constitutive activation of the JAK-STAT pathway. Our aim is not to be expansive but to highlight emerging ideas towards preventive therapy in a modern view of JAK-STAT inhibitors. A series of agents with different specificities against different members of the JAK family of proteins is currently undergoing evaluation in clinical trials. Here we give a summary of how JAK-STAT inhibitors function and a detailed review of current clinical drugs for managing cancer as a new therapeutic approach.


Assuntos
Neoplasias Hematológicas , Neoplasias , Humanos , Janus Quinases/genética , Janus Quinases/metabolismo , Transdução de Sinais , Fatores de Transcrição STAT/genética , Fatores de Transcrição STAT/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias Hematológicas/tratamento farmacológico , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/metabolismo
11.
JAMA Oncol ; 9(8): 1066-1073, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37289451

RESUMO

Importance: Preoperative stereotactic radiosurgery (SRS) has been demonstrated as a feasible alternative to postoperative SRS for resectable brain metastases (BMs) with potential benefits in adverse radiation effects (AREs) and meningeal disease (MD). However, mature large-cohort multicenter data are lacking. Objective: To evaluate preoperative SRS outcomes and prognostic factors from a large international multicenter cohort (Preoperative Radiosurgery for Brain Metastases-PROPS-BM). Design, Setting, and Participants: This multicenter cohort study included patients with BMs from solid cancers, of which at least 1 lesion received preoperative SRS and a planned resection, from 8 institutions. Radiosurgery to synchronous intact BMs was allowed. Exclusion criteria included prior or planned whole-brain radiotherapy and no cranial imaging follow-up. Patients were treated between 2005 and 2021, with most treated between 2017 and 2021. Exposures: Preoperative SRS to a median dose to 15 Gy in 1 fraction or 24 Gy in 3 fractions delivered at a median (IQR) of 2 (1-4) days before resection. Main Outcomes and Measures: The primary end points were cavity local recurrence (LR), MD, ARE, overall survival (OS), and multivariable analysis of prognostic factors associated with these outcomes. Results: The study cohort included 404 patients (214 women [53%]; median [IQR] age, 60.6 [54.0-69.6] years) with 416 resected index lesions. The 2-year cavity LR rate was 13.7%. Systemic disease status, extent of resection, SRS fractionation, type of surgery (piecemeal vs en bloc), and primary tumor type were associated with cavity LR risk. The 2-year MD rate was 5.8%, with extent of resection, primary tumor type, and posterior fossa location being associated with MD risk. The 2-year any-grade ARE rate was 7.4%, with target margin expansion greater than 1 mm and melanoma primary being associated with ARE risk. Median OS was 17.2 months (95% CI, 14.1-21.3 months), with systemic disease status, extent of resection, and primary tumor type being the strongest prognostic factors associated with OS. Conclusions and Relevance: In this cohort study, the rates of cavity LR, ARE, and MD after preoperative SRS were found to be notably low. Several tumor and treatment factors were identified that are associated with risk of cavity LR, ARE, MD, and OS after treatment with preoperative SRS. A phase 3 randomized clinical trial of preoperative vs postoperative SRS (NRG BN012) has began enrolling (NCT05438212).


Assuntos
Neoplasias Encefálicas , Radiocirurgia , Humanos , Feminino , Pessoa de Meia-Idade , Radiocirurgia/métodos , Estudos de Coortes , Estudos Retrospectivos , Fatores de Risco , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirurgia , Neoplasias Encefálicas/secundário
13.
Res Sq ; 2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36993444

RESUMO

The CD8+ T-cell response is prognostic for survival outcomes in several tumor types. However, whether this extends to tumors in the brain, an organ with barriers to T cell entry, remains unclear. Here, we analyzed immune infiltration in 67 brain metastasis (BrM) and found high frequencies of PD1+ TCF1+ stem-like CD8+ T-cells and TCF1- effector-like cells. Importantly, the stem-like cells aggregate with antigen presenting cells in immune niches, and niches were prognostic for local disease control. Standard of care for BrM is resection followed by stereotactic radiosurgery (SRS), so to determine SRS's impact on the BrM immune response, we examined 76 BrM treated with pre-operative SRS (pSRS). pSRS acutely reduced CD8+ T cells at 3 days. However, CD8+ T cells rebounded by day 6, driven by increased frequency of effector-like cells. This suggests that the immune response in BrM can be regenerated rapidly, likely by the local TCF1+ stem-like population.

14.
Psychiatry Res Neuroimaging ; 328: 111580, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36481591

RESUMO

Corpus callosum (CC) is the largest commissural white matter bundle in the brain, responsible for the integration of information between hemispheres. Reduction in the size of the CC structure has been predominantly reported in children with autism spectrum disorder (ASD) compared to typically developing children (TD). However, most of these studies are based on high-functioning individuals with ASD but not on an inclusive sample of individuals with ASD with varying abilities. Our current study aimed to examine the CC morphometry between children with ASD and TD in the Indian population. We also compared CC morphometry in autistic children with autism severity, verbal IQ (VIQ) and full-scale IQ (FSIQ). T1-weighted structural images were acquired using a 3T MRI scanner to examine the CC measures in 62 ASD and 17 TD children. The length and height of the CC and the width of genu were decreased in children with ASD compared to TD. There was no significant difference in CC measures based on autism severity, VIQ or FSIQ among children with ASD. To our knowledge, this is the first neuroimaging study to include a significant number (n = 56) of low-functioning ASD children. Our findings suggest the atypical interhemispheric connectivity of CC in ASD.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Substância Branca , Humanos , Criança , Corpo Caloso/diagnóstico por imagem , Transtorno Autístico/diagnóstico por imagem , Transtorno do Espectro Autista/diagnóstico por imagem , Encéfalo , Substância Branca/diagnóstico por imagem
15.
J Mater Chem C Mater ; 11(43): 15357-15365, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-38304018

RESUMO

Recently, metal halides have shown great potential for applications such as solar energy harvesting, light emission, and ionizing radiation detection. In this work, we report the preparation, structural, thermal, and electronic properties of a new zero-dimensional (0D) halide (TEP)InBr4 (where TEP is tetraethylphosphonium organic cation, C8H20P+). (TEP)InBr4 single crystals are obtained within a few days of continuous crystal growth time via a solution growth methodology. (TEP)InBr4 shows a relatively large optical bandgap energy of 4.32 eV and a low thermal conductivity between 0.33±0.05 and 0.45±0.07 W/m-K. Based on the density functional theory (DFT) calculations, the highest occupied molecular orbitals (HOMOs) of (TEP)InBr4 are dominated by the Br states, while the lowest unoccupied molecular orbitals (LUMOs) are constituted by both In and Br states. (TEP)InBr4 single crystals exhibit a semiconductor resistivity of 1.73×1013 Ω·cm and a mobility-lifetime (mu-tau) product of 2.07×10-5 cm2/V. Finally, a prototype (TEP)InBr4 single crystal-based X-ray detector with a detection sensitivity of 569.85 uCGy-1cm-2 (at electrical field E=100 V/mm) was fabricated, indicating the potential use of (TEP)InBr4 for radiation detection applications.

16.
ACS Appl Mater Interfaces ; 14(36): 40738-40748, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36053500

RESUMO

Understanding the interplay between various design strategies (for instance, bonding heterogeneity and lone pair induced anharmonicity) to achieve ultralow lattice thermal conductivity (κl) is indispensable for discovering novel functional materials for thermal energy applications. In the present study, we investigate layered PbXF (X = Cl, Br, I), which offers bonding heterogeneity through the layered crystal structure, anharmonicity through the Pb2+ 6s2 lone pair, and phonon softening through the mass difference between F and Pb/X. The weak interlayer van der Waals bonding and the strong intralayer ionic bonding with partial covalent bonding result in a significant bonding heterogeneity and a poor phonon transport in the out-of-plane direction. Large average Grüneisen parameters (≥2.5) demonstrate strong anharmonicity. The computed phonon dispersions show flat bands, which suggest short phonon lifetimes, especially for PbIF. Enhanced Born effective charges are due to cross-band-gap hybridization. PbIF shows lattice instability at a small volume expansion of 0.1%. The κl values obtained by the two channel transport model are 20-50% higher than those obtained by solving the Boltzmann transport equation. Overall, ultralow κl values are found at 300 K, especially for PbIF. We propose that the interplay of bonding heterogeneity, lone pair induced anharmonicity, and constituent elements with high mass difference aids the design of low κl materials for thermal energy applications.

17.
ACS Appl Mater Interfaces ; 14(12): 14753-14763, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35289597

RESUMO

In this work, we demonstrate that edge oxidation of graphene can enable larger enhancement in thermal conductivity (k) of graphene nanoplatelet (GnP)/polyetherimide (PEI) composites relative to oxidation of the basal plane of graphene. Edge oxidation offers the advantage of leaving the basal plane of graphene intact, preserving its high in-plane thermal conductivity (kin > 2000 W m-1 K-1), while, simultaneously, the oxygen groups introduced on the graphene edge enhance interfacial thermal conductance through hydrogen bonding with oxygen groups of PEI, enhancing the overall polymer composite thermal conductivity. Edge oxidation is achieved in this work by oxidizing graphene in the presence of sodium chlorate and hydrogen peroxide, thereby introducing an excess of carboxyl groups on the edge of graphene. Basal plane oxidation of graphene, on the other hand, is achieved through the Hummers method, which distorts the sp2 carbon-carbon network of graphene, dramatically lowering its intrinsic thermal conductivity, causing the BGO/PEI (BGO = basal-plane oxidized graphene or basal-plane-functionalized graphene oxide) composite's k value to be even lower than pristine GnP/PEI composite's k value. The resulting thermal conductivity of the EGO/PEI (EGO = edge-oxidized graphene or edge-functionalized graphene oxide) composite is found to be enhanced by 18%, whereas that of the BGO/PEI composite is diminished by 57%, with respect to the pristine GnP/PEI composite with 10 wt % GnP content. Two-dimensional Raman mapping of GnPs is used to confirm and distinguish the location of oxygen functional groups on graphene. The superior effect of edge bonding presented in this work can lead to fundamentally novel pathways for achieving high thermal conductivity polymer composites.

18.
Ann Surg Oncol ; 29(5): 3291-3301, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35015183

RESUMO

BACKGROUND: Prognostic nomograms for patients with resected extremity soft tissue sarcoma (STS) include the Sarculator and Memorial Sloan Kettering (MSKCC) nomograms. We sought to validate these two nomograms within a large, modern, multi-institutional cohort of resected primary extremity STS patients. METHODS: Resected primary extremity STS patients from 2000 to 2017 were identified across nine high-volume U.S. institutions. Predicted 5- and 10-year overall survival (OS) and distant metastases cumulative incidence (DMCI), and 4-, 8-, and 12-year disease-specific survival (DSS) were calculated with Sarculator and MSKCC nomograms, respectively. Predicted survival probabilities stratified in quintiles were compared in calibration plots to observed survival assessed by Kaplan-Meier estimates. Cumulative incidence was estimated for DMCI. Harrell's concordance index (C-index) assessed discriminative ability of nomograms. RESULTS: A total of 1326 patients underwent resection of primary extremity STS. Common histologies included: undifferentiated pleomorphic sarcoma (35%), fibrosarcoma (13%), and leiomyosarcoma (9%). Median tumor size was 8.0 cm (IQR 4.5-13.0). Tumor grade distribution was: Grade 1 (13%), Grade 2 (9%), Grade 3 (78%). Median OS was 172 months, with estimated 5- and 10-year OS of 70% and 58%. C-indices for 5- and 10-year OS (Sarculator) were 0.72 (95% CI 0.70-0.75) and 0.73 (95% CI 0.70-0.75), and 0.72 (95% CI 0.69-0.75) for 5- and 10-year DMCI. C-indices for 4-, 8-, and 12-year DSS (MSKCC) were 0.71 (95% CI 0.68-0.75). Calibration plots showed good prognostication across all outcomes. CONCLUSIONS: Sarculator and MSKCC nomograms demonstrated good prognostic ability for survival and recurrence outcomes in a modern, multi-institutional validation cohort of resected primary extremity STS patients. External validation of these nomograms supports their ongoing incorporation into clinical practice.


Assuntos
Sarcoma , Neoplasias de Tecidos Moles , Extremidades/patologia , Extremidades/cirurgia , Humanos , Nomogramas , Prognóstico , Sarcoma/patologia , Neoplasias de Tecidos Moles/cirurgia
19.
Pract Radiat Oncol ; 12(2): e101-e109, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34848379

RESUMO

PURPOSE: Volumetric modulated arc therapy (VMAT) craniospinal irradiation (CSI) has been shown to have significant dosimetric advantages compared to 3-dimensional conformal therapy but is a technically complex process. We sought to develop a guide for all aspects of the VMAT CSI process and report patient dosimetry results. METHODS AND MATERIALS: We initiated VMAT CSI in 2017 and have regularly revised our standard operating procedure for this process since then. Herein, we report a detailed template for the entire VMAT CSI process from initial patient setup and immobilization at time of computed tomography (CT) simulation to contouring and treatment planning, quality assurance, and therapy delivery. The records of 12 patients who were treated with VMAT CSI were also retrospectively reviewed. RESULTS: Patient age ranged from 2 to 59 years with 5 pediatric patients (age <18 years), 5 young adults (age 18-35 years), and 2 older adults (age >35 years). The majority of patients (67%) had medulloblastoma. CSI dose ranged from 21.6 to 36 Gy, with a median of 36 Gy. The median CSI planning target volume was 2383 cc with a median V95% of 99.8% and median 0.03 cc hotspot of 112.5%. The average V107% was 7.4% and the average conformality index was 1.01. CONCLUSIONS: VMAT CSI has potentially significant dosimetric and acute toxicity advantages compared to 3-dimensional conformal. However, proper procedures need to be in place throughout the process in order to be able to realize these potential advantages. We herein describe our detailed standard operating procedure for VMAT CSI. Recognizing the scarcity of proton beam centers in many areas, VMAT CSI represents a feasible treatment with more widespread availability.


Assuntos
Neoplasias Cerebelares , Radiação Cranioespinal , Radioterapia de Intensidade Modulada , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Radiação Cranioespinal/métodos , Humanos , Pessoa de Meia-Idade , Órgãos em Risco/efeitos da radiação , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Estudos Retrospectivos , Adulto Jovem
20.
Ann Surg Oncol ; 29(2): 1327-1333, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34625880

RESUMO

BACKGROUND: For locally advanced esophageal squamous cell carcinoma (ESCC), chemoradiation (ChemoRT) followed by surgery offers the best chance of cure, with a 35-50% pathologic complete response (pCR) rate. Given the morbidity of esophagectomy and the possibility of pCR with ChemoRT, a 'watch and wait' strategy has been proposed, particularly for squamous cell carcinoma. The ability to accurately predict which patients will have pCR from ChemoRT is critical in treatment decision making. This study assessed positron emission tomography (PET) in predicting pCR after neoadjuvant ChemoRT for ESCC. METHODS: ESCC patients treated with ChemoRT followed by surgery were identified. Maximum standard uptake value (SUV), metabolic tumor volume, total lesion glycolysis, and first-order textual features of standard deviation, kurtosis and skewness were measured from PET. Univariable and multivariable generalized linear method analyses were performed. A metabolic complete response (mCR) was defined as a post-therapy PET scan with maximum SUV < 4.0. RESULTS: Twenty-seven patients underwent ChemoRT followed by surgery, with overall pCR seen in 11 (41%) patients and radiographic mCR seen in 12 (44%) patients. Final pathology for these 12 patients revealed pCR (ypT0N0M0) in 5 (42%) patients and persistent disease in 7 (58%) patients. Univariate analysis did not reveal PET parameters predictive of pCR. CONCLUSION: Treatment of ESCC with ChemoRT often results in a robust clinical response. Among patients with an mCR after ChemoRT, disease persistence was found in 58%. The inability of PET to predict pCR is important in the context of a 'watch and wait' strategy for ESCC treated with ChemoRT.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Quimiorradioterapia , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/terapia , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/terapia , Esofagectomia , Fluordesoxiglucose F18 , Humanos , Terapia Neoadjuvante , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos/uso terapêutico , Estudos Retrospectivos
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