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1.
Radiat Environ Biophys ; 63(3): 443-454, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38809486

RESUMO

This study aimed to evaluate the modulated arc therapy (mARC) technique as a planning and treatment option for hippocampal sparing whole brain radiotherapy (HS-WBRT) following the Radiation Therapy Oncology Group (RTOG) 0933 dosimetric criteria. Computed tomography (CT) and magnetic resonance imaging (MRI) were selected retrospectively for 15 patients. Two types of plans were created for each patient, namely an intensity-modulated radiation therapy (IMRT) and a mARC plan. IMRT and mARC plans were compared in terms of plan quality indices, absorbed dose to organs at risk (OARs), number of monitor units (MUs), and treatment time. All plans in both techniques were considered clinically acceptable for treatment. However, IMRT plans presented a higher conformity (p = 0.01) as well as a higher homogeneity as compared to mARC plans, but this difference was not statistically significant (p > 0.05). In terms of the preservation of the hippocampus, it was observed that the IMRT plans achieved significantly lower doses for both 100% of its volume and for its maximum dose (p < 0.001). The evaluation of the remaining OARs showed that the IMRT technique resulted in lower doses, and significant differences were observed for the following organs: left cochlea (p < 0.001), left eye (p < 0.001), right eye (p = 0.03), both lenses of the eye (p < 0.001), and right optic nerve (p = 0.02). Despite these differences, the absolute differences in all dosimetric parameters were low enough to bear any clinical relevance. A drastic (close to 65%) and significant (p < 0.001) decrease was observed in the number of MUs for the mARC plans. This resulted in a substantial decrease in treatment time (60.45%, p < 0.001). It is concluded that the mARC technique is a feasible planning and treatment solution for HS-WBRT that meets the RTOG 0933 criteria. The main advantage of using mARC over IMRT for HS-WBRT is the considerable reduction in MUs and treatment time.


Assuntos
Neoplasias Encefálicas , Hipocampo , Órgãos em Risco , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Humanos , Radioterapia de Intensidade Modulada/métodos , Hipocampo/efeitos da radiação , Hipocampo/diagnóstico por imagem , Planejamento da Radioterapia Assistida por Computador/métodos , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/diagnóstico por imagem , Masculino , Órgãos em Risco/efeitos da radiação , Feminino , Pessoa de Meia-Idade , Adulto , Dosagem Radioterapêutica , Estudos Retrospectivos , Idoso , Tratamentos com Preservação do Órgão/métodos , Irradiação Craniana/métodos
2.
J Therm Biol ; 123: 103944, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39137568

RESUMO

This study aimed to predict the annual herd milk yield, lactation, and reproductive cycle stages in a high-input dairy herd in a zone with prolonged thermal stress. Also, the impact of climatic conditions on milk yield and productive and reproductive status was assessed. An autoregressive integrated moving average (ARIMA) model was used in data fitting to predict future monthly herd milk yield and reproductive status using data from 2014 to 2020. Based on the annual total milk output, the highest predicted percentage of milk yield based on the yearly milk production was in February (9.1%; 95% CI = 8.3-9.9) and the lowest in August (6.9%; 95% CI = 6.0-7.9). The predicted highest percentage of pregnant cows for 2021 was in May (61.8; 95% CI = 53.0-70.5) and the lowest for November (33.2%; 95% CI = 19.9-46.5). The monthly percentage of dry cows in this study showed a steady trend across years; the predicted highest percentage was in September (20.1%; CI = 16.4-23.7) and the lowest in March (7.5%; 4.0-11.0). The predicted days in milk (DIM) were lower in September (158; CI = 103-213) and highest in May (220; 95% CI = 181-259). Percentage of calvings was seasonal, with the predicted maximum percentage of calvings occurring in September (10.3%; CI = 8.0-12.5) and the minimum in April (3.2%; CI = 1.0-5.5). The highest predicted culling rate for the year ensuing the present data occurred in November (4.3%; 95% CI = 3.2-5.4) and the lowest in April (2.5%; 95% CI = 1.4-3.5). It was concluded that meteorological factors strongly influenced rhythms of monthly milk yield and reproductive status. Also, ARIMA models robustly estimated and forecasted productive and reproductive events in a dairy herd in a hot environment.


Assuntos
Indústria de Laticínios , Lactação , Leite , Reprodução , Estações do Ano , Animais , Bovinos/fisiologia , Feminino , Leite/metabolismo , Temperatura Alta , Gravidez , Clima
3.
Appl Opt ; 62(34): 9089-9095, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38108746

RESUMO

Aluminum thin films were deposited on a 3D prototype employing the direct current magnetron sputtering technique to fabricate a lightweight 3D first surface mirror. Before the aluminizing, the surface of the prototypes was evaluated with interferometry and atomic force microscope (AFM). The thin films were characterized using profilometry, UV-Vis spectroscopy, x-ray diffraction, AFM, x-ray photoelectron spectroscopy (XPS), and scanning electron microscopy. High adherence and homogeneous deposition of the aluminum's thin films were achieved. In addition, the purity of the material was confirmed by XPS analysis.

4.
Radiat Environ Biophys ; 61(3): 407-423, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35819511

RESUMO

The clinical information on the relationship between the cardiac contact distance (CCD), the maximum dose (Dmax) delivered to the left anterior descending (LAD) coronary artery and the mean heart dose has mostly focused on patients with breast-conserving surgery (BCS), being scarce in postmastectomy patients. The aim of this study is to determine the association between the CCD and the Dmax delivered to the LAD. The secondary objective was to evaluate the dosimetric results of comparing three-dimensional conformal radiotherapy (3D-CRT) to intensity-modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) techniques for post mastectomized breast cancer patients with irradiation to the left chest wall. 53 cases of women who received adjuvant standard fractionated postmastectomy radiotherapy (PMRT) were used. Three types of plans were created for each patient: 3D-CRT, seven equidistant IMRT fields, and four partial VMAT arcs. Correlations were evaluated using Pearson's correlation coefficient. Plans made with IMRT and VMAT showed improved homogeneity and conformity. Associations between CCD and Dmax to LAD were positive for all three plan types. Compared to 3D-CRT, the modulated intensity plans obtained better dose homogeneity and conformity to the target volume. The LAD and heart doses were significantly lower for IMRT and VMAT plans. The CCD can be used as a predictor of the maximum and mean doses of the LAD. Modulated intensity techniques allow for better dose distribution and dose reduction to the heart and LAD.


Assuntos
Neoplasias da Mama , Radioterapia de Intensidade Modulada , Neoplasias da Mama/radioterapia , Vasos Coronários , Feminino , Humanos , Mastectomia , Órgãos em Risco/efeitos da radiação , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador
5.
Georgian Med News ; (330): 99-105, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36427851

RESUMO

Coronavirus disease 2019 (Covid-19) active cases continue to demand the development of safe and effective treatments. This is the first clinical trial to evaluate the safety and efficacy of oral thymic peptides. ; We conducted a nonrandomized phase 2 trial with a historic control group to evaluate the safety and efficacy of a daily 250-mg oral dose of thymic peptides in the treatment of hospitalized Covid-19 patients. Comparisons based on standard care from registry data were performed after propensity score matching. The primary outcomes were survival, time to recovery, and number of participants with treatment-related adverse events or side effects by day 20. ; A total of 44 patients were analyzed in this study: 22 in the thymic peptide group and 22 in the standard care group. There were no deaths in the intervention group compared to 24% mortality in standard care by day 20 (log-rank P=0.02). Kaplan-Meier analysis showed a significantly shorter time to recovery by day 20 in the thymic peptide group than in the standard care group (median, 6 days vs. 12 days; hazard ratio for recovery, 2.75 [95% confidence interval, 1.34 to 5.62]; log-rank P=0.002). No side effects or adverse events were reported. ; In patients hospitalized with Covid-19, the use of thymic peptides resulted in no side effects, adverse events, or deaths by day 20. Compared with the registry data, a significantly shorter time to recovery and mortality reduction were measured.


Assuntos
Tratamento Farmacológico da COVID-19 , Peptídeos , Humanos , Honduras , Estimativa de Kaplan-Meier , Peptídeos/efeitos adversos , Modelos de Riscos Proporcionais
6.
Clin Exp Immunol ; 204(1): 78-95, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33306195

RESUMO

Immune checkpoint therapy to reverse natural killer (NK) and T cell exhaustion has emerged as a promising treatment in various cancers. While anti-programmed cell death 1 (PD-1) pembrolizumab has recently gained Food and Drug Administration (FDA) approval for use in recurrent or metastatic cervical cancer, other checkpoint molecules, such as T cell immunoreceptor with immunoglobulin (Ig) and immunoreceptor tyrosine-based inhibition motif (ITIM) domains (TIGIT) and T cell immunoglobulin and mucin-domain containing-3 (Tim-3), have yet to be fully explored in this disease. We report expression of TIGIT, Tim-3 and PD-1 on subsets of peripheral blood NK (CD56dim/neg CD16bright/dim/neg and CD56bright CD16dim/neg ) and T cells. The percentages of these cells were increased in women with cervical cancer and pre-malignant lesions. PD-1+ NK and T cells were likely to co-express TIGIT and/or Tim-3. These cells, with an apparently 'exhausted' phenotype, were augmented in patients. A subset of cells were also natural killer group 2 member D (NKG2D)- and DNAX accessory molecule 1 (DNAM-1)-positive. PD-1int and PD-1high T cells were notably increased in cervical cancer. Soluble programmed cell death ligand 1 (PD-L1) was higher in cancer patient blood versus healthy donors and we observed a positive correlation between sPD-L1 and PD-1+ T cells in women with low-grade lesions. Within the cancer group, there were no significant correlations between sPD-L1 levels and cervical cancer stage. However, when comparing cancer versus healthy donors, we observed an inverse association between sPD-L1 and total T cells and a correlation between sPD-L1 and CD56dim NK cells. Our results may show an overview of the immune response towards pre-cancerous lesions and cervical cancer, perhaps giving an early clue as to whom to administer blocking therapies. The increase of multiple checkpoint markers may aid in identifying patients uniquely responsive to combined antibody therapies.


Assuntos
Antígeno B7-H1/metabolismo , Células Matadoras Naturais/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Linfócitos T/metabolismo , Neoplasias do Colo do Útero/metabolismo , Adulto , Antígenos de Diferenciação de Linfócitos T/metabolismo , Antígeno CD56/metabolismo , Feminino , Citometria de Fluxo/métodos , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Humanos , Células Matadoras Naturais/imunologia , Pessoa de Meia-Idade , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Receptores Imunológicos/metabolismo , Linfócitos T/imunologia , Neoplasias do Colo do Útero/imunologia , Neoplasias do Colo do Útero/patologia , Adulto Jovem
7.
J Biol Regul Homeost Agents ; 35(2 Suppl. 1): 79-88, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34281304

RESUMO

In the last decades, the presence of peri-implant diseases (PD) has increased. One of the therapies currently used is probiotics with Lactobacillus reuteri (LR). The aim of this article is to determinate, through a systematic review and meta-analysis, the clinical effectiveness of LR in the treatment of PD. We searched the literature until January 2021, in the biomedical databases: Pubmed, Embase, Scielo, Science Direct, Scopus, SIGLE, LILACS, Google Scholar and Cochrane Central Registry of Clinical Trials. The selection criteria of the studies were: randomized controlled clinical trials, without language and time restriction, reporting the clinical effects (depth to probing, plaque index and bleeding index) of the LR in the PD treatment. The risk of study bias was analyzed through the Cochrane tool for randomized studies using Review Manager software. The search strategy resulted in 6 articles of which four investigated peri-implantitis and three peri-implant mucositis. All studies reported that there was a difference in the depth of the probing in the treatment of PD, in favor of the group using LR, though not always achieving significance. The use of LR can be clinically effective in terms of pocket depth reduction in the treatment of PD.


Assuntos
Implantes Dentários , Limosilactobacillus reuteri , Peri-Implantite , Probióticos , Humanos , Peri-Implantite/terapia , Resultado do Tratamento
8.
Radiat Environ Biophys ; 60(4): 653-662, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34363120

RESUMO

The aim of this study was to investigate the effect of a hybrid technique which results from combining intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) for the treatment of cervical cancer patients. Plans made with the hybrid technique and pure IMRT and VMAT were retrospectively compared in 20 patients with cervical cancer at different stages. All plans were made using the same contours based on the original computed tomography (CT) scans. Conformity (CI) and homogeneity (HI) indices of the planning target volumes (PTVs) were calculated for each technique in order to evaluate plan quality. All techniques were compared in terms of dose to organs at risk (OARs), number of monitor units (MUs) and treatment time. It turned out that plans made with the hybrid technique had improved dose conformity and homogeneity compared to plans made only with IMRT and VMAT (p < 0.001). Regarding the OARs, the maximum dose (Dmax) delivered to the bladder, rectum and femoral heads was lower for the hybrid plans compared to the IMRT and VMAT plans (p < 0.001). The volumes irradiated to doses of 50 Gy (V50Gy) for rectum, bladder and bowel were lower for the hybrid plans (p < 0.001, p = 0.002). Furthermore, the treatment time and MU values for the hybrid plans were found to be between of the values for the IMRT and VMAT plans. It is concluded that, as compared to IMRT and VMAT plans, the hybrid plan technique allowed a better conformity and homogeneity for the dose distribution in the PTV and a dose reduction to the OARs.


Assuntos
Radioterapia de Intensidade Modulada , Neoplasias do Colo do Útero , Feminino , Humanos , Órgãos em Risco , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Estudos Retrospectivos , Neoplasias do Colo do Útero/radioterapia
9.
Clin Oral Investig ; 23(12): 4205-4212, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30806798

RESUMO

To determine Toll-like receptors (TLR)2 and TLR4 expression levels and associate them with matrix metalloproteinases (MMPs) in asymptomatic apical periodontitis (AAP), symptomatic apical periodontitis (SAP), and healthy controls. Apical tissue/lesion samples were obtained from chronic AAP (n = 35) and SAP (n = 29), and healthy periodontal ligament (HPL, n = 10) with indication of tooth extraction, respectively. mRNA expression levels of TLR2, TLR4, MMP-1, MMP-2, MMP-8, and MMP-13 were determined by real-time reverse-transcription polymerase chain reaction. The data were analyzed with Kruskal-Wallis and Dunn's pot hoc test (p < 0.05). The correlation coefficient was obtained using the Spearman correlation (p < 0.05). TLR2, MMP-1, MMP-2, and MMP-13 mRNA levels were the highest in SAP followed by AAP and controls (p < 0.05). TLR4 and MMP-8 were over expressed in AAP and SAP compared to HPL (p < 0.05). TLR2 positively correlated with TLR4, MMP-1, MMP-8, and MMP-13 in SAP (p < 0.05). TLR2 and TLR4 are overexpressed in apical lesions versus healthy periodontal ligament and correlate with collagenolytic MMPs. Particularly, TLR2 is overexpressed in SAP in association with MMP-1, MMP-8, and MMP-13. Our results suggest that the activation of TLR2 along with MMP overexpression might contribute to SAP clinical presentation and progression. TLRs, MMPs, and their interaction can explain the clinical presentations and evolution of apical periodontitis and might represent key targets for new diagnostic and treatment approaches.


Assuntos
Metaloproteinases da Matriz/metabolismo , Periodontite Periapical/metabolismo , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Estudos Transversais , Humanos , Periodontite Periapical/patologia , Ligamento Periodontal/efeitos dos fármacos , Ligamento Periodontal/metabolismo , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/genética , Ápice Dentário/metabolismo
10.
Lupus ; 26(2): 200-203, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27416847

RESUMO

Objective Hepcidin regulates iron availability and may be responsible for the anemia of chronic disease because it is induced by interleukin-6. This study investigated the IL-6-hepcidin-hemoglobin axis in patients with lupus. Methods IL-6 and hepcidin were measured in serial serum samples collected before, during and after lupus flares by specific ELISAs. Results During renal and non-renal SLE flare cycles IL-6 did not predict hepcidin and hepcidin did not predict hemoglobin. When lupus nephritis patients were in remission, IL-6 and hepcidin were correlated, but hepcidin and hemoglobin were not. Conclusion Hepcidin does not contribute significantly to anemia during active lupus.


Assuntos
Hemoglobinas/metabolismo , Hepcidinas/sangue , Interleucina-6/sangue , Lúpus Eritematoso Sistêmico/sangue , Nefrite Lúpica/sangue , Anemia/sangue , Anemia/diagnóstico , Biomarcadores/sangue , Progressão da Doença , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Lúpus Eritematoso Sistêmico/diagnóstico , Nefrite Lúpica/diagnóstico , Masculino , Ohio , Estudos Prospectivos , Fatores de Tempo
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