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1.
Rep Pract Oncol Radiother ; 28(3): 322-331, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37795405

RESUMO

Background: The current standard of treatment for locally advanced cervical cancer is concurrent chemo-radiation with improved overall survival (OS) by 6% with manageable toxicities. The cisplatin 40 mg/m2 given weekly is the widely practiced regimen for 4-6 cycles concurrently with irradiation. Materials and methods: Two hundred and twelve patients with histologically proven squamous cell carcinoma of cervix with stages IIB to IIIB were enrolled between 2007-2011. External beam radiation dose of 45 Gy in 25 fractions was delivered over 5 weeks. Brachytherapy was delivered by manual afterloading cesium-137 (Cs137) low dose brachytherapy (LDR) using modified Fletcher suit intracavitary applicators to a total dose of 30 Gy to Point A or interstitial template to dose of 21 Gy/3 fractions with remote afterloading iridium-192 (Ir192) high dose brachytherapy (HDR). Patients were randomized to arm A receiving 40 mg/m2 of concurrent cisplatin weekly and arm B receiving 100 mg/m2 of concurrent cisplatin triweekly. Results: One hundred and nine patients were randomized to weekly cisplatin and one hundred and three patients to triweekly cisplatin at the end of recruitment. At ten years, the OS was higher in the weekly arm (79.8%) compared to triweekly arm (70.9%). Disease free survival (DFS) was almost equal (76.1% and 73.8%) in the weekly and three-weekly arms. There is definite significance in overall DFS with patients receiving the cumulative cisplatin doses of more than 250 mg (p = 0.028). The patients with more than 45 years of age had better overall survival (OS) (79%) with statistical significance 31 (p = 0.020). Conclusion: Both cisplatin based triweekly and weekly concurrent chemotherapy are equally effective in terms of OS and DFS.

2.
Ann Oncol ; 33(8): 814-823, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35513244

RESUMO

BACKGROUND: Difference in pathologic complete response (pCR) rate after neoadjuvant chemotherapy does not capture the impact of treatment on downstaging of residual cancer in the experimental arm. We developed a method to compare the entire distribution of residual cancer burden (RCB) values between clinical trial arms to better quantify the differences in cytotoxic efficacy of treatments. PATIENTS AND METHODS: The Treatment Efficacy Score (TES) reflects the area between the weighted cumulative distribution functions of RCB values from two trial arms. TES is based on a modified Kolmogorov-Smirnov test with added weight function to capture the importance of high RCB values and uses the area under the difference between two distribution functions as a statistical metric. The higher the TES the greater the shift to lower RCB values in the experimental arm. We developed TES from the durvalumab + olaparib arm (n = 72) and corresponding controls (n = 282) of the I-SPY2 trial. The 11 other experimental arms and control cohorts (n = 947) were used as validation sets to assess the performance of TES. We compared TES to Kolmogorov-Smirnov, Mann-Whitney, and Fisher's exact tests to identify trial arms with higher cytotoxic efficacy and assessed associations with trial arm level survival differences. Significance was assessed with a permutation test. RESULTS: In the validation set, TES identified arms with a higher pCR rate but was more accurate to identify regimens as less effective if treatment did not reduce the frequency of high RCB values, even if the pCR rate improved. The correlation between TES and survival was higher than the correlation between the pCR rate difference and survival. CONCLUSIONS: TES quantifies the difference between the entire distribution of pathologic responses observed in trial arms and could serve as a better early surrogate to predict trial arm level survival differences than pCR rate difference alone.


Assuntos
Antineoplásicos , Neoplasias da Mama , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/patologia , Feminino , Humanos , Terapia Neoadjuvante , Neoplasia Residual/tratamento farmacológico , Neoplasia Residual/patologia , Resultado do Tratamento
3.
Ann Oncol ; 32(5): 642-651, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33617937

RESUMO

BACKGROUND: We proposed that a test for sensitivity to the adjuvant endocrine therapy component of treatment for patients with stage II-III breast cancer (SET2,3) should measure transcription related to estrogen and progesterone receptors (SETER/PR index) adjusted for a baseline prognostic index (BPI) combining clinical tumor and nodal stage with molecular subtype by RNA4 (ESR1, PGR, ERBB2, and AURKA). PATIENTS AND METHODS: Patients with clinically high-risk, hormone receptor-positive (HR+), human epidermal growth factor receptor 2 (HER2)-negative (HR+/HER2-) breast cancer received neoadjuvant taxane-anthracycline chemotherapy, surgery with measurement of residual cancer burden (RCB), and then adjuvant endocrine therapy. SET2,3 was measured from pre-treatment tumor biopsies, evaluated first in an MD Anderson Cancer Center (MDACC) cohort (n = 307, 11 years' follow-up, U133A microarrays), cut point was determined, and then independent, blinded evaluation was carried out in the I-SPY2 trial (n = 268, high-risk MammaPrint result, 3.8 years' follow-up, Agilent-44K microarrays, NCI Clinical Trials ID: NCT01042379). Primary outcome measure was distant relapse-free survival. Multivariate Cox regression models tested prognostic independence of SET2,3 relative to RCB and other molecular prognostic signatures, and whether other prognostic signatures could substitute for SETER/PR or RNA4 components of SET2,3. RESULTS: SET2,3 added independent prognostic information to RCB in the MDACC cohort: SET2,3 [hazard ratio (HR) 0.23, P = 0.004] and RCB (HR 1.77, P < 0.001); and the I-SPY2 trial: SET2,3 (HR 0.27, P = 0.031) and RCB (HR 1.68, P = 0.008). SET2,3 provided similar prognostic information irrespective of whether RCB-II or RCB-III after chemotherapy, and in both luminal subtypes. Conversely, RCB was most strongly prognostic in cancers with low SET2,3 status (MDACC P < 0.001, I-SPY2 P < 0.001). Other molecular signatures were not independently prognostic; they could effectively substitute for RNA4 subtype within the BPI component of SET2,3, but they could not effectively substitute for SETER/PR index. CONCLUSIONS: SET2,3 added independent prognostic information to chemotherapy response (RCB) and baseline prognostic score or subtype. Approximately 40% of patients with clinically high-risk HR+/HER2- disease had high SET2,3 and could be considered for clinical trials of neoadjuvant endocrine-based treatment.


Assuntos
Neoplasias da Mama , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/genética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Feminino , Hormônios/uso terapêutico , Humanos , Terapia Neoadjuvante , Recidiva Local de Neoplasia , Prognóstico , Receptor ErbB-2/genética , Receptores de Progesterona/genética
4.
Neurourol Urodyn ; 40(1): 158-167, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32990349

RESUMO

AIM: Because bacterial cystitis is common in women with refractory detrusor overactivity, the aim was to compare the efficacy of 6 weeks of rotating antibiotics versus placebo, in conjunction with an anticholinergic, in controlling the symptoms of urge incontinence. METHODS: In a multicenter phase IIb double-blinded randomized placebo-controlled trial, women with urodynamically proven refractory detrusor overactivity were randomized in a 2:1 ratio of antibiotics versus placebo for 6 weeks, in addition to darifenacin for 6 months. Any woman with disabling cystitis symptoms was given appropriate antibiotics ("clinical override"). The primary outcome was the degree of urge incontinence change at 6 weeks and 6 months on 24-h pad test. Secondary outcomes were changes in leaks and voids per day measured on 3-day bladder diary and quality of life measures. Microbiological data were collected at all visits. RESULTS: Although 278 women were screened, only 36 were randomized and 33 (91.7%) completed the trial. Leakage on 24-h pad test decreased at 6 months by 75 g in patients receiving antibiotics versus 35 g in placebo. Cure of urge incontinence occurred at 6 months in 10/21 (48%) of antibiotics versus 2/12 (17%) of placebo. Clinical override, necessitating treatment of cystitis, occurred in 41.6% of placebo versus 16.7% of the antibiotic group by 6 months. CONCLUSION: Despite the small sample size, the study showed a significant reduction in pad leakage and leaks per day over 24 h in the active treatment group over a 6-month period. Nearly half of patients on placebo had disabling urinary tract infection symptoms that required clinical override treatment.


Assuntos
Antibacterianos/uso terapêutico , Bexiga Urinária Hiperativa/tratamento farmacológico , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade , Resultado do Tratamento
5.
Bioprocess Biosyst Eng ; 44(1): 57-66, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32767112

RESUMO

A new design of cross-linked enzyme aggregates (CLEAs) of Burkholderia cepacia lipase (BCL) based mainly on the use of lignocellulosic residue of palm fiber as an additive was proposed. Different parameters for the preparation of active CLEAs in the hydrolysis of olive oil, such as precipitation agents, crosslinking agent concentration, additives, and coating agents were investigated. The highest activity yield (121.1 ± 0.1%) and volumetric activity (1578.1 ± 2.5 U/mL) were achieved for CLEAs prepared using the combination of a coating step with Triton® X-100 and polyethyleneimine plus the use of palm fiber as an additive. The variations of the secondary structures of BCL-CLEAs were analyzed by second-derivative infrared spectra, mainly indicating a reduction of the α-helix structure, which was responsible for the lipase activation in the supramolecular structure of the CLEAs. Thus, these results provided evidence of an innovative design of BCL-CLEAs as a sustainable and biocompatible opportunity for biotechnology applications.


Assuntos
Proteínas de Bactérias/química , Burkholderia cepacia/enzimologia , Enzimas Imobilizadas/química , Lipase/química , Estabilidade Enzimática , Cinética
6.
Rep Pract Oncol Radiother ; 26(6): 948-954, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34992867

RESUMO

BACKGROUND: Addition of chemotherapy to radiation has improved 5-year survival by 6%. However, the optimal dose and schedule of concurrent cisplatin is not well defined, though widely accepted practice is the weekly schedule of 40 mg/m2 for 5 weeks. Repeated admissions for weekly cisplatin drain the limited resources in high volume centres. We intended to study the compliance and toxicity of two cisplatin schedules in our patients diagnosed with carcinoma cervix. MATERIALS AND METHODS: Between 2007-2011, 212 patients, histologically proven squamous cell carcinoma with stages IIB to IIIB were randomized into two arms. All patients were planned for external beam radiotherapy 45 Gy/25 frs over 5 weeks followed by Intracavitary or Interstitial brachytherapy to a total BED dose of 75-85 Gy. Single agent cisplatin given concomitantly, was scheduled weekly (40 mg/m2/cycle, 5 cycles) in an arm A and three weekly (100 mg/m2/cycle, 2 cycles) in an arm B. Toxicity and compliance were evaluated weekly according to the RTOG guidelines. Analysis of the compiled data was done using SSPS version 20. RESULTS: Of the evaluable 212, 109 patients received weekly cisplatin chemotherapy and 103 patients received three weekly cisplatin. The most common acute toxicity observed was grade I-II leucopoenia. The upper and lower gastrointestinal reactions were high in three weekly arms, which was statistically significant (57% and 42.7%, p < 0.05). Proctitis was observed in 10% of patients in both of the arms and only two patients had Gr1 Cystitis after 6 months of treatment. CONCLUSIONS: Tri-weekly cisplatin based concurrent chemoradiation can be adopted in high volume centres with manageable haematological and gastrointestinal acute toxicities.

7.
Phys Chem Chem Phys ; 22(16): 9098-9109, 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32300765

RESUMO

Li and Mn-rich Li1+xNiyCozMnwO2 (LMR-NMC, 0 < x < 0.2; w > 0.5) materials remain commercially relevant owing to their high specific capacity. Due to this stoichiometry, their synthesis forms always at least two phases: monoclinic Li2MnO3 and rhombohedral LiNiaCobMncO2 (a = b = c = 1) layered moieties. However, a complete understanding of their complex crystal structure has not yet been fully realized. The monoclinic phase may become electrochemically active only at high potentials (>4.6 V vs. Li). To complicate matters even more, it has been shown that the electrochemical performance of these materials, having formally the same stoichiometry, can vary with the chosen method of material synthesis. Identification of the chemical and/or structural reasons for these variations in performance is crucial to ensure the promotion of these important cathode materials towards a practical use. Yet most methods of analysis cannot distinguish the subtle, localized variations that account for such differences. Here, solid state 6,7Li NMR was found to be successful in identifying several distinctions between compounds with identical chemical formulae. Many distinctions can be made, and even suggested to account for some of the differences in the electrochemical behaviors noted for the differently prepared materials.

8.
Ann Oncol ; 30(3): 405-411, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30475947

RESUMO

BACKGROUND: Standard first-line treatment of metastatic triple-negative breast cancer (mTNBC) is chemotherapy. However, outcomes are poor, and new treatment options are needed. In cohort B of the phase II KEYNOTE-086 study, we evaluated pembrolizumab as first-line therapy for patients with PD-L1-positive mTNBC. PATIENTS AND METHODS: Eligible patients had centrally confirmed mTNBC, no prior systemic anticancer therapy for metastatic disease, measurable disease at baseline per RECIST v1.1 by central review, no radiographic evidence of central nervous system metastases, and a tumor PD-L1 combined positive score ≥1. Patients received pembrolizumab 200 mg intravenously every 3 weeks for up to 2 years. The primary end point was safety. Secondary end points included objective response rate, disease control rate (percentage of patients with complete or partial response or stable disease for ≥24 weeks), duration of response, progression-free survival and overall survival. RESULTS: All 84 patients enrolled were women, and 73 (86.9%) received prior (neo)adjuvant therapy. Fifty-three (63.1%) patients had treatment-related adverse events (AEs), including 8 patients (9.5%) with grade 3 severity; no patients experienced grade 4 AEs or died because of treatment-related AEs. Four patients had a complete response and 14 had a partial response, for an objective response rate of 21.4% (95% CI 13.9-31.4). Of the 13 patients with stable disease, 2 had stable disease lasting ≥24 weeks, for a disease control rate of 23.8% (95% CI 15.9-34.0). At data cut-off, 8 of 18 (44.4%) responses were ongoing, and median duration of response was 10.4 months (range 4.2 to 19.2+). Median progression-free survival was 2.1 months (95% CI 2.0-2.2), and median overall survival was 18.0 months (95% CI 12.9-23.0). CONCLUSIONS: Pembrolizumab monotherapy had a manageable safety profile and showed durable antitumor activity as first-line therapy for patients with PD-L1-positive mTNBC. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT02447003.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Antígeno B7-H1/genética , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/efeitos adversos , Estudos de Coortes , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Intervalo Livre de Progressão , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia
9.
Ann Oncol ; 30(3): 397-404, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30475950

RESUMO

BACKGROUND: Treatment options for previously treated metastatic triple-negative breast cancer (mTNBC) are limited. In cohort A of the phase II KEYNOTE-086 study, we evaluated pembrolizumab as second or later line of treatment for patients with mTNBC. PATIENTS AND METHODS: Eligible patients had centrally confirmed mTNBC, ≥1 systemic therapy for metastatic disease, prior treatment with anthracycline and taxane in any disease setting, and progression on or after the most recent therapy. Patients received pembrolizumab 200 mg intravenously every 3 weeks for up to 2 years. Primary end points were objective response rate in the total and PD-L1-positive populations, and safety. Secondary end points included duration of response, disease control rate (percentage of patients with complete or partial response or stable disease for ≥24 weeks), progression-free survival, and overall survival. RESULTS: All enrolled patients (N = 170) were women, 61.8% had PD-L1-positive tumors, and 43.5% had received ≥3 previous lines of therapy for metastatic disease. ORR (95% CI) was 5.3% (2.7-9.9) in the total and 5.7% (2.4-12.2) in the PD-L1-positive populations. Disease control rate (95% CI) was 7.6% (4.4-12.7) and 9.5% (5.1-16.8), respectively. Median duration of response was not reached in the total (range, 1.2+-21.5+) and in the PD-L1-positive (range, 6.3-21.5+) populations. Median PFS was 2.0 months (95% CI, 1.9-2.0), and the 6-month rate was 14.9%. Median OS was 9.0 months (95% CI, 7.6-11.2), and the 6-month rate was 69.1%. Treatment-related adverse events occurred in 103 (60.6%) patients, including 22 (12.9%) with grade 3 or 4 AEs. There were no deaths due to AEs. CONCLUSIONS: Pembrolizumab monotherapy demonstrated durable antitumor activity in a subset of patients with previously treated mTNBC and had a manageable safety profile. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT02447003.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Antígeno B7-H1/genética , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antraciclinas/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Hidrocarbonetos Aromáticos com Pontes/administração & dosagem , Estudos de Coortes , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Intervalo Livre de Progressão , Taxoides/administração & dosagem , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia
10.
Ann Oncol ; 30(6): 927-933, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30903140

RESUMO

BACKGROUND: HER2-positive (+) breast cancers, defined by HER2 overexpression and/or amplification, are often addicted to HER2 to maintain their malignant phenotype. Yet, some HER2+ tumors do not benefit from anti-HER2 therapy. We hypothesize that HER2 amplification levels and PI3K pathway activation are key determinants of response to HER2-targeted treatments without chemotherapy. PATIENTS AND METHODS: Baseline HER2+ tumors from patients treated with neoadjuvant lapatinib plus trastuzumab [with endocrine therapy for estrogen receptor (ER)+ tumors] in TBCRC006 (NCT00548184) were evaluated in a central laboratory for HER2 amplification by fluorescence in situ hybridization (FISH) (n = 56). HER2 copy number (CN) and FISH ratios, and PI3K pathway status, defined by PIK3CA mutations or PTEN levels by immunohistochemistry were available for 41 tumors. Results were correlated with pathologic complete response (pCR; no residual invasive tumor in breast). RESULTS: Thirteen of the 56 patients (23%) achieved pCR. None of the 11 patients with HER2 ratio <4 and/or CN <10 achieved pCR, whereas 13/45 patients (29%) with HER2 ratio ≥4 and/or CN ≥10 attained pCR (P = 0.0513). Of the 18 patients with tumors expressing high PTEN or wild-type (WT) PIK3CA (intact PI3K pathway), 7 (39%) achieved pCR, compared with 1/23 (4%) with PI3K pathway alterations (P = 0.0133). Seven of the 16 patients (44%) with HER2 ratio ≥4 and intact PI3K pathway achieved pCR, whereas only 1/25 (4%) patients not meeting these criteria achieved pCR (P = 0.0031). CONCLUSIONS: Our findings suggest that there is a clinical subtype in breast cancer with high HER2 amplification and intact PI3K pathway that is especially sensitive to HER2-targeted therapies without chemotherapy. A combination of HER2 FISH ratio and PI3K pathway status warrants validation to identify patients who may be treated with HER2-targeted therapy without chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Receptor ErbB-2/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Classe I de Fosfatidilinositol 3-Quinases/genética , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Feminino , Seguimentos , Amplificação de Genes , Humanos , Hibridização in Situ Fluorescente , Lapatinib/administração & dosagem , Terapia Neoadjuvante , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Prognóstico , Receptor ErbB-2/antagonistas & inibidores , Receptor ErbB-2/genética , Indução de Remissão , Trastuzumab/administração & dosagem
11.
Magn Reson Chem ; 56(2): 62-72, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28921712

RESUMO

Recently, NMR spectroscopy has been emerging out as a powerful tool to study the structure and dynamics of ionic liquids (ILs) and ILs-Li+ salt mixtures. This mini-review primarily focuses on the applications of various NMR spectroscopic techniques such as self-diffusion measurements, NMR relaxometry, two-dimensional NMR, and other novel NMR approaches to study the structure and dynamics of ILs and its mixtures with lithium salts. Copyright © 2017 John Wiley & Sons, Ltd.

12.
Orthod Craniofac Res ; 20 Suppl 1: 162-166, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28643904

RESUMO

OBJECTIVE: To study the effects of intermittent parathyroid hormone (PTH [1-34]) on the mandibular condylar cartilage (MCC) and subchondral bone in adult female mice. MATERIALS AND METHODS: Twenty-two, 20-week-old female mice were used for in vivo experiments. The experimental mice (n=11) received daily intraperitoneal injections of PTH [1-34] for 3 weeks, while control mice (n=11) received intraperitoneal injections of 0.9% saline solution. Mice were euthanized and then micro-computed tomography (micro-CT); histology and immunostaining were carried out to assess the response. RESULTS: Intermittent PTH [1-34] led to early MCC breakdown and surface irregularities. Micro-CT analyses indicated that PTH [1-34] treatment led to increased bone volume fraction, tissue density and trabecular thickness, while decreasing the trabecular spacing. Histological analyses showed decreased proteoglycan secretion, increased bone turnover (TRAP staining) and increased mineralization. Furthermore, PTH [1-34] treatment showed increased apoptosis of the cells. Our immunohistochemistry showed increased expression of pSMAD158 in the MCC and subchondral bone with PTH administration, whereas sclerostin (SOST) expression was decreased. CONCLUSIONS: Intermittent PTH [1-34] results in early mineralization of the MCC, which may result in cartilage degeneration. Our results identified a novel mechanism by which PTH [1-34] induces alteration in the microarchitecture of the MCC and the subchondral bone.


Assuntos
Cartilagem Articular/efeitos dos fármacos , Côndilo Mandibular/efeitos dos fármacos , Hormônio Paratireóideo/farmacologia , Animais , Remodelação Óssea/efeitos dos fármacos , Cartilagem Articular/diagnóstico por imagem , Cartilagem Articular/patologia , Feminino , Côndilo Mandibular/diagnóstico por imagem , Côndilo Mandibular/patologia , Camundongos , Hormônio Paratireóideo/administração & dosagem , Microtomografia por Raio-X
13.
Osteoarthritis Cartilage ; 24(2): 335-44, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26362410

RESUMO

OBJECTIVES: The generation of transgenic mice expressing green fluorescent proteins (GFPs) has greatly aided our understanding of the development of connective tissues such as bone and cartilage. Perturbation of a biological system such as the temporomandibular joint (TMJ) within its adaptive remodeling capacity is particularly useful in analyzing cellular lineage progression. The objectives of this study were to determine: (i) if GFP reporters expressed in the TMJ indicate the different stages of cell maturation in fibrocartilage and (ii) how mechanical loading affects cellular response in different regions of the cartilage. DESIGN/METHODS: Four-week-old transgenic mice harboring combinations of fluorescent reporters (Dkk3-eGFP, Col1a1(3.6 kb)-GFPcyan, Col1a1(3.6 kb)-GFPtpz, Col2a1-GFPcyan, and Col10a1-RFPcherry) were used to analyze the expression pattern of transgenes in the mandibular condylar cartilage (MCC). To study the effect of TMJ loading, animals were subjected to forced mouth opening with custom springs exerting 50 g force for 1 h/day for 5 days. Dynamic mineralization and cellular proliferation (EdU-labeling) were assessed in loaded vs control mice. RESULTS: Dkk3 expression was seen in the superficial zone of the MCC, followed by Col1 in the cartilage zone, Col2 in the prehypertrophic zone, and Col10 in the hypertrophic zone at and below the tidemark. TMJ loading increased expression of the GFP reporters and EdU-labeling of cells in the cartilage, resulting in a thickness increase of all layers of the cartilage. In addition, mineral apposition increased resulting in Col10 expression by unmineralized cells above the tidemark. CONCLUSION: The TMJ responded to static loading by forming thicker cartilage through adaptive remodeling.


Assuntos
Condrócitos/metabolismo , Colágeno Tipo II/metabolismo , Colágeno Tipo I/metabolismo , Colágeno Tipo X/metabolismo , Fibrocartilagem/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Articulação Temporomandibular/metabolismo , Suporte de Carga , Proteínas Adaptadoras de Transdução de Sinal , Animais , Fenômenos Biomecânicos , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Linhagem da Célula , Cadeia alfa 1 do Colágeno Tipo I , Fibrocartilagem/patologia , Proteínas de Fluorescência Verde/genética , Proteínas Luminescentes/genética , Côndilo Mandibular/metabolismo , Côndilo Mandibular/patologia , Camundongos , Camundongos Transgênicos , Tamanho do Órgão , Articulação Temporomandibular/patologia , Proteína Vermelha Fluorescente
14.
Phys Chem Chem Phys ; 18(37): 25801-25805, 2016 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-27711646

RESUMO

An unusual linear dependency of viscosity with temperature has been observed in aqueous solutions of 1-octyl-3-methylimidazolium-based ionic liquids because of the ion induced structural transition which leads to the violation of both the Stokes-Einstein and fractional Stokes-Einstein equations, suggesting the presence of dynamic heterogeneity in the system.

15.
Orthod Craniofac Res ; 17(4): 239-48, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24924469

RESUMO

OBJECTIVE: To examine the expression of bone sialoprotein (BSP) and apoptosis in an in vivo orthodontic relapse model. MATERIALS AND METHODS: Male mice (10-12 weeks old), either transgenic [green fluorescent protein (GFP) driven by the BSP promoter] or wild type, were used in this study. To achieve orthodontic tooth movement (OTM), maxillary right first molars were moved mesially using closed-coil springs. Animals were divided into an OTM group (14 days continuous orthodontic force - 11 animals) or Relapse group (10 days of force application followed by 4 days of relapse - 8 animals). The control group was comprised of the contralateral maxillary molars. The periodontal ligament (PDL) was analyzed in areas of compression and tension for transgenic expression, osteoclast localization, and the presence of apoptotic cells. RESULTS: There was a significant decrease in GFP-labeled cells on the compression and tension sides of the PDL in the OTM group compared with control. In the relapse group, GFP-labeled cells were significantly decreased only on the old compression side. Osteoclasts were localized on the compression side of the OTM group, whereas in the Relapse group, they were present on both sides. PDL apoptosis significantly increased on the compression side in OTM and Relapse groups. CONCLUSION: Both OTM and Relapse groups exhibited a decreased number of GFP-labeled cells in areas of compression and tension. There was significant PDL apoptosis in regions under compressive forces following OTM and to a lesser extent following relapse.


Assuntos
Apoptose/fisiologia , Sialoproteína de Ligação à Integrina/análise , Ligamento Periodontal/patologia , Técnicas de Movimentação Dentária/métodos , Fosfatase Ácida/análise , Processo Alveolar/química , Processo Alveolar/patologia , Animais , Remodelação Óssea/fisiologia , Cemento Dentário/química , Cemento Dentário/patologia , Marcação In Situ das Extremidades Cortadas , Isoenzimas/análise , Masculino , Maxila/patologia , Camundongos , Camundongos Transgênicos , Dente Molar/patologia , Osteoblastos/química , Osteoblastos/patologia , Osteoclastos/patologia , Osteócitos/química , Osteócitos/patologia , Ligamento Periodontal/química , Pressão , Recidiva , Estresse Mecânico , Fosfatase Ácida Resistente a Tartarato , Técnicas de Movimentação Dentária/instrumentação , Microtomografia por Raio-X/métodos
16.
Breast Cancer Res Treat ; 136(2): 355-63, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22245973

RESUMO

Preclinical models suggested that activating mutations of the PIK3CA gene are associated with sensitivity to inhibitors of the mammalian target of rapamycin (mTOR). In breast cancers, PIK3CA mutations are associated with estrogen receptor (ER) positivity. We therefore performed an open-label single arm phase II study of the rapamycin analog, temsirolimus, at a dose of 25 mg weekly, in women with pretreated breast cancers that were positive for ER, PR, or HER2. Archived formalin-fixed paraffin embedded tumor was collected for immunohistochemical evaluation of components of the PI3K/Akt/mTOR pathway and PIK3CA mutation analysis. Thirty-one patients were enrolled. There were no major objective responses; however, three patients had stable disease for over 24 weeks. Twenty-three tumor samples were available for mutational analysis. There were five tumors with PIK3CA mutations; no association was found between prolonged stable disease and PIK3CA mutation or any immunohistochemical marker. There was a trend toward improved progression free survival (PFS) for patients with positive nuclear staining for phospho-Akt308. One patient remains on study four and a half years after starting therapy; her tumor did not have a PIK3CA mutation. We conclude that single agent temsirolimus has minimal activity in a population of women with heavily pretreated breast cancer. We found no evidence that either absence of immunohistochemical staining for PTEN or mutations in the hotspot domains of PIK3CA in the primary tumor were associated with clinical benefit.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Inibidores de Proteínas Quinases/uso terapêutico , Sirolimo/análogos & derivados , Antineoplásicos/administração & dosagem , Neoplasias da Mama/genética , Progressão da Doença , Feminino , Humanos , Mutação , Metástase Neoplásica , Inibidores de Proteínas Quinases/administração & dosagem , Sirolimo/administração & dosagem , Sirolimo/uso terapêutico , Resultado do Tratamento
17.
Orthod Craniofac Res ; 15(1): 52-61, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22264327

RESUMO

OBJECTIVE: To evaluate the effects of orthodontic tooth movement on the promoter expression of collagen type 1 (3.6Col1), bone sialoprotein (BSP) and alpha-smooth muscle actin (αSMA) in the periodontal ligament (PDL) using transgenic mice containing transgenes of these promoters fused to green fluorescent proteins (GFP). MATERIALS AND METHODS: The maxillary first molars of 10-12 week-old transgenic mice were loaded with 10-12 g of force for 12, 48 h, or 7 days. Mice were transgenic for one of the following GFP-tagged bone markers of osteoblast lineage cells: 3.6-kb fragment of the rat collagen type 1 promoter (3.6Col1), BSP or α-smooth muscle actin (αSMA). Loaded molars under compression and tension were compared with contra-lateral unloaded controls. RESULTS: On the compression side of the PDL, orthodontic tooth movement caused a significant decrease in GFP expression of all the promoters at each time point. On the tension side, there was a significant increase in BSP-GFP expression, 12 h following loading compared to the contralateral unloaded controls. CONCLUSIONS: An in vivo tooth movement model using transgenic mice with promoter-GFP constructs provides an efficient and effective way of investigating the cellular events underlying orthodontic tooth movement. PDL cells may undergo decreased differentiation in response to the compressive force.


Assuntos
Actinas/genética , Colágeno Tipo I/genética , Sialoproteína de Ligação à Integrina/genética , Ligamento Periodontal/metabolismo , Regiões Promotoras Genéticas/genética , Técnicas de Movimentação Dentária , Actinas/análise , Animais , Diferenciação Celular/genética , Linhagem da Célula , Colágeno Tipo I/análise , Genes Reporter/genética , Proteínas de Fluorescência Verde , Sialoproteína de Ligação à Integrina/análise , Substâncias Luminescentes , Maxila/patologia , Camundongos , Camundongos Transgênicos , Dente Molar/patologia , Osteoblastos/patologia , Ligamento Periodontal/patologia , Ratos , Estresse Mecânico , Fatores de Tempo , Técnicas de Movimentação Dentária/instrumentação , Raiz Dentária/patologia , Transgenes/genética
18.
Sci Rep ; 11(1): 18708, 2021 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34548531

RESUMO

People with diabetes are at risk of chronic complications and novel biomarkers, such as Advanced glycation end-products (AGEs) may help stratify this risk. We assessed whether plasma low-molecular weight AGEs, also known as LMW-fluorophores (LMW-F), are associated with risk factors, predict complications, and are altered by fenofibrate in adults with type 2 diabetes. Plasma LMW-F were quantified at baseline, after six weeks fenofibrate, and one year post-randomisation to fenofibrate or placebo. LMW-F associations with existing and new composite vascular complications were determined, and effects of fenofibrate assessed. LMW-F correlated positively with age, glycated haemoglobin (HbA1c), pulse pressure, kidney dysfunction and inflammation; and negatively with urate, body mass index, oxidative stress and leptin, albeit weakly (r = 0.04-0.16, all p < 0.01). Independent determinants of LMW-F included smoking, diastolic blood pressure, prior cardiovascular disease or microvascular complications, Caucasian ethnicity, kidney function, HbA1c and diabetes duration (all p ≤ 0.01). Baseline LMW-F tertiles correlated with on-trial macrovascular and microvascular complications (trend p < 0.001) on univariate analyses only. Six weeks of fenofibrate increased LMW-F levels by 21% (p < 0.001). In conclusion, LMW-F levels correlate with many risk factors and chronic diabetes complications, and are increased with fenofibrate. LMW-F tertiles predict complications, but not independently of traditional risk factors.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Fenofibrato/uso terapêutico , Corantes Fluorescentes/química , Hipolipemiantes/uso terapêutico , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Peso Molecular
19.
J Basic Clin Physiol Pharmacol ; 20(1): 89-97, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19601399

RESUMO

Eleven diagnosed diabetic patients and fifteen healthy age-matched controls were subjected to six standardized cardiovascular autonomic reflex function tests. The aim of the study was to identify the best sympathetic and parasympathetic autonomic function tests in diabetic patients and to determine their sensitivity. Several diabetic patients showed an abnormal response to various autonomic function tests. Among the three sympathetic tests studied, the coefficient of variation of all tests was found to vary and hence most sensitive test could not be determined. The heart-rate response to standing was found to be the most sensitive as it showed the lowest coefficient of variation. More parasympathetic than sympathetic tests showed abnormal responses in diabetics, particularly for heart rate responses to a deep breathing test. The results indicate that all autonomic function tests have to be performed for a proper evaluation/diagnosis of diabetic autonomic neuropathy.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Pressão Sanguínea , Diabetes Mellitus/fisiopatologia , Neuropatias Diabéticas/diagnóstico , Frequência Cardíaca , Adulto , Feminino , Humanos , Masculino , Sensibilidade e Especificidade
20.
J Basic Clin Physiol Pharmacol ; 20(2): 187-96, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19662721

RESUMO

Eleven diagnosed diabetic patients and fifteen healthy age-matched control subjects were subjected to six standardized cardiovascular autonomic reflex function tests. The aim of the study was to identify the best sympathetic and parasympathetic autonomic function tests in diabetic patients and to determine their sensitivity. Several diabetic patients showed an abnormal response to various autonomic function tests. Among the three sympathetic tests studied, the coefficient of variation of all tests was found to vary; hence, the most sensitive test could not be determined. The heart-rate response to standing was found to be the most sensitive as it showed the lowest coefficient of variation. More parasympathetic than sympathetic tests showed abnormal responses in diabetics, particularly for heart rate responses to a deep breathing test. The results indicate that all autonomic function tests have to be performed for a proper evaluation/diagnosis of diabetic autonomic neuropathy.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Pressão Sanguínea , Diabetes Mellitus/fisiopatologia , Neuropatias Diabéticas/diagnóstico , Frequência Cardíaca , Adulto , Feminino , Humanos , Masculino , Sensibilidade e Especificidade
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