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2.
Biomed Phys Eng Express ; 9(3)2023 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-36821850

RESUMO

Periodontitis is a highly prevalent infectious disease that causes the progressive destruction of the periodontal supporting tissues. If left untreated, it can lead to tooth loss impairing oral function, aesthetics, and the patient's overall quality of life. Guided and Bone Tissue Regeneration (GTR/BTR) are surgical therapies based on the placement of a membrane that prevents epithelial growth into the defect, allowing the periodontal/bone cells (including stem cells) to regenerate or restore the affected tissues. The success of these therapies is commonly affected by the local bacterial colonization of the membrane area and its fast biodegradation, causing postoperative infections and a premature rupture of the membrane limiting the regeneration process. This study presents the antibacterial and osteogenic differentiation properties of polycaprolactone-gelatin (PCL-G) electrospun membranes modified with ZnO nanoparticles (ZnO-NPs). The membranes´ chemical composition, surface roughness, biodegradation, water wettability, and mechanical properties under simulated physiological conditions, were analyzed by the close relationship with their biological properties. The PCL-G membranes modified with 1, 3, and 6% w/w of ZnO-NPs showed a significant reduction in the planktonic and biofilm formation of four clinically relevant bacteria;A. actinomycetemcomitansserotype b, P. gingivalis,E. coli, andS. epidermidis. Additionally, the membranes presented appropriate mechanical properties and biodegradation rates to be potentially used in clinical treatments. Notably, the membranes modified with the lowest concentration of ZnO-NPs (1% w/w) stimulated the production of osteoblast markers and calcium deposits in human bone marrow-derived mesenchymal stem cells (BM-MSC) and were biocompatible to human osteoblasts cells (hFOB). These results suggest that the PCL-G membranes with 1% w/w of ZnO-NPs are high-potential candidates for GTR/BTR treatments, as they were the most effective in terms of better antibacterial effectiveness at a lower NPs-concentration while creating a favorable cellular microenvironment for bone growth.


Assuntos
Osteogênese , Óxido de Zinco , Humanos , Gelatina/química , Óxido de Zinco/farmacologia , Alicerces Teciduais/química , Escherichia coli , Qualidade de Vida , Regeneração Óssea , Antibacterianos/farmacologia , Diferenciação Celular
3.
Biomed Mater ; 15(3): 035006, 2020 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-31995538

RESUMO

The bacterial colonization of absorbable membranes used for guided tissue regeneration (GTR), as well as their rapid degradation that can cause their rupture, are considered the major reasons for clinical failure. To address this, composite membranes of polycaprolactone (PCL) and gelatin (Gel) loaded with zinc oxide nanoparticles (ZnO-NPs; 1, 3 and 6 wt% relative to PCL content) were fabricated by electrospinning. To fabricate homogeneous fibrillar membranes, acetic acid was used as a sole common solvent to enhance the miscibility of PCL and Gel in the electrospinning solutions. The effects of ZnO-NPs in the physico-chemical, mechanical and in vitro biological properties of composite membranes were studied. The composite membranes showed adequate mechanical properties to offer a satisfactory clinical manipulation and an excellent conformability to the defect site while their degradation rate seemed to be appropriate to allow successful regeneration of periodontal defects. The presence of ZnO-NPs in the composite membranes significantly decreased the planktonic and the biofilm growth of the Staphylococcus aureus over time. Finally, the viability of human osteoblasts and human gingival fibroblasts exposed to the composite membranes with 1 and 3 wt% of ZnO-NPs indicated that those membranes are not expected to negatively influence the ability of periodontal cells to repopulate the defect site during GTR treatments. The results here obtained suggest that composite membranes of PCL and Gel loaded with ZnO-NPs have the potential to be used as structurally stable GTR membranes with local antibacterial properties intended for enhancing clinical treatments.


Assuntos
Regeneração Tecidual Guiada/métodos , Nanopartículas Metálicas/química , Staphylococcus aureus/efeitos dos fármacos , Engenharia Tecidual/métodos , Óxido de Zinco/química , Antibacterianos/farmacologia , Sobrevivência Celular , Fibroblastos/efeitos dos fármacos , Gelatina/química , Gengiva/efeitos dos fármacos , Gengiva/metabolismo , Humanos , Membranas Artificiais , Testes de Sensibilidade Microbiana , Nanotecnologia/métodos , Osteoblastos/efeitos dos fármacos , Poliésteres/química , Staphylococcus aureus/metabolismo , Resistência à Tração , Termogravimetria
4.
Biomed Mater ; 15(3): 035001, 2020 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-31899893

RESUMO

Blends of natural and synthetic polymers have recently attracted great attention as scaffolds for tissue engineering applications due to their favorable biological and mechanical properties. Nevertheless, phase-separation of blend components is an important challenge facing the development of electrospun homogeneous fibrillar natural-synthetic polymers scaffolds; phase-separation can produce significant detrimental effects for scaffolds fabricated by electrospinning. In the present study, blends of gelatin (Gel; natural polymer) and polycaprolactone (PCL; synthetic polymer), containing 30 and 45 wt% Gel, were prepared using acetic acid as a 'green' sole solvent to straightforwardly produce appropriate single-step Gel-PCL solutions for electrospinning. Miscibility of Gel and PCL in the scaffolds was assessed and the morphology, chemical composition and structural and solid-state properties of the scaffolds were thoroughly investigated. Results showed that the two polymers proved miscible under the single-step solution process used and that the electrospun scaffolds presented suitable properties for potential skin tissue engineering applications. Viability, metabolic activity and protein expression of human fibroblasts cultured on the Gel-PCL scaffolds were evaluated using LIVE/DEAD (calcein/ethidium homodimer), MTT-Formazan and immunocytochemistry assays, respectively. In vitro results showed that the electrospun Gel-PCL scaffolds enhanced cell viability and proliferation in comparison to PCL scaffolds. Furthermore, scaffolds allowed fibroblasts expression of extracellular matrix proteins, tropoelastin and collagen Type I, in a similar way to positive controls. Results indicated the feasibility of the single-step solution process used herein to obtain homogeneous electrospun Gel-PCL scaffolds with Gel content ≥30 wt% and potential properties to be used as scaffolds for skin tissue engineering applications for wound healing.


Assuntos
Fibroblastos/efeitos dos fármacos , Gelatina/química , Poliésteres/química , Pele/efeitos dos fármacos , Engenharia Tecidual/instrumentação , Alicerces Teciduais , Sobrevivência Celular , Colágeno Tipo I/metabolismo , Condutividade Elétrica , Matriz Extracelular/metabolismo , Temperatura Alta , Humanos , Concentração de Íons de Hidrogênio , Polímeros/química , Pele/metabolismo , Solventes/química , Espectrofotometria Infravermelho , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Mecânico , Resistência à Tração , Termogravimetria , Engenharia Tecidual/métodos , Tropoelastina/química , Viscosidade , Cicatrização , Difração de Raios X
5.
ACS Omega ; 4(5): 7953-7962, 2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31459884

RESUMO

The motor dysfunction featured by patients aggrieved by Parkinson's disease (PD) results from the reduction of dopamine (DA) availability in the caudate nucleus (CN). Restituting CN DA levels is therefore essential to ameliorate PD motor deficits. In this regard, nanotechnology may offer solutions to restore CN DA availability. DA, however, can be rapidly oxidized into toxic compounds if made available in situ, unprotected. Then, we tested whether a semicrystalline TiO2 lattice, implanted into the CN of 6-hydroxydopamine (6-OHDA)-lesioned, hemiparkinsonian rats, was able to release DA during a time window sufficient to attenuate motor symptoms while protecting it from the ongoing oxidation. Accordingly, implanted semicrystalline TiO2 lattices released incremental amounts of DA into the CN of lesioned rats. Motor symptoms were already attenuated by the 1st month and significantly reduced 2 months after implantation. These effects were specific since TiO2 lattices alone did not modify motor symptoms in lesioned rats. DA-unloaded or -loaded TiO2 lattices did not produce obvious symptoms of systemic or neurological toxicity nor significantly increased CN lipid peroxidation in implanted, lesioned rats at the time of sacrifice. Our results thus support that loaded TiO2 lattices are capable of releasing DA while protecting it from the ongoing oxidation when implanted into the brain. Their implantation does not cause noticeable systemic or local toxicity. On the contrary, they attenuated motor symptoms in hemiparkinsonian rats.

6.
Nanomedicine ; 14(5): 1695-1706, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29673978

RESUMO

ZnO and Zn acetate nanoparticles were embedded in polycaprolactone coaxial-fibers and uniaxial-fibers matrices to develop potential antibacterial nanocomposite wound dressings (mats). Morphology, composition, wettability, crystallinity and fiber structure of mats were characterized. Antibacterial properties of mats were tested against E. coli and S. aureus by turbidity and MTT assays. The effect of UVA illumination (prior to bacteria inoculation) on mats' antibacterial activity was also studied. Results showed that a coaxial-fibers design maintained nanoparticles distributed in the outer-shell of fibers and, in general, enhanced the antibacterial effect of the mats, in comparison to conventional uniaxial-fibers mats. Results indicated that mats simultaneously inhibited planktonic and biofilm bacterial growth by, probably, two main antibacterial mechanisms; 1) release of Zn2+ ions (mainly from Zn acetate nanoparticles) and 2) photocatalytic oxidative processes exerted by ZnO nanoparticles. Antibacterial properties of mats were significantly improved by coaxial-fibers design and exposure to UVA-light prior to bacteria inoculation.


Assuntos
Antibacterianos/administração & dosagem , Escherichia coli/efeitos dos fármacos , Nanofibras/administração & dosagem , Poliésteres/química , Staphylococcus aureus/efeitos dos fármacos , Acetato de Zinco/administração & dosagem , Óxido de Zinco/administração & dosagem , Antibacterianos/química , Bandagens , Escherichia coli/crescimento & desenvolvimento , Nanofibras/química , Nanotecnologia , Staphylococcus aureus/crescimento & desenvolvimento , Acetato de Zinco/química , Óxido de Zinco/química
7.
Rev Med Inst Mex Seguro Soc ; 49(3): 335-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21839004

RESUMO

We report the case of a 82 year-old woman with hyperosmolar hyperglycemic state (HHS) associated with hypernatremia, who was treated using 0.2 % sodium chloride in 5 % dextrose in water which resulted in the amelioration of the neurological symptoms in a short period of time, followed the decrease in serum glucose and the serum sodium, consequently the serum osmolality. We discuss the advantages and usefulness of 0.2 % sodium chloride in 5 % dextrose in water in this syndrome and emphasize its importance in the treatment. We reviewed the literature on HHS and we assume that this case reported was treated with hypotomic solution without subsequent neurological damage.


Assuntos
Hiperglicemia/complicações , Hipernatremia/etiologia , Idoso de 80 Anos ou mais , Feminino , Humanos , Concentração Osmolar , Síndrome
8.
Brachytherapy ; 10(1): 44-50, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-20591748

RESUMO

PURPOSE: To test the hypothesis that cross-linked hyaluronan gel (Hylaform) does not affect the quality of life (QOL) of prostate cancer patients undergoing radiotherapy. METHODS AND MATERIALS: Thirty-five patients with early stage prostate cancer underwent high-dose-rate brachytherapy to 2200 cGy and intensity modulated radiation therapy to 5040 cGy on a prospective study. Thirty patients received a single transperineal injection of 9-mL Hylaform between the prostate and rectum under transrectal ultrasound guidance immediately before the start of radiotherapy. Hylaform increased the separation between the prostate and rectum by 6-19 mm (median, 13 mm) at the start of radiotherapy. Five patients did not receive Hylaform and served as controls. We assessed gastrointestinal-related QOL using Expanded Prostate Cancer Index Composite Bowel Bother scores immediately before the start of and during the last week of radiotherapy. RESULTS: At the beginning of intensity modulated radiation therapy, daily mean rectal doses were 74±8 cGy (mean±standard deviation) and 105±25 cGy (mean±standard deviation) with vs. without Hylaform, respectively (p=0.01). Expanded Prostate Cancer Index Composite Bowel Bother scores decreased by 0±3 (mean±standard deviation) and 11±14 (mean±standard deviation) in patients who did and did not receive Hylaform, respectively (p=0.03). CONCLUSIONS: Hylaform increased the separation between the prostate and rectum and decreased the mean rectal dose, thereby improving the gastrointestinal-related acute QOL of prostate cancer patients undergoing radiotherapy. Patients will be followed up long term to determine if the improvement in acute QOL also translates into an improvement in late QOL.


Assuntos
Ácido Hialurônico/análogos & derivados , Neoplasias da Próstata/radioterapia , Qualidade de Vida , Viscossuplementos/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Braquiterapia/efeitos adversos , Trato Gastrointestinal/fisiopatologia , Trato Gastrointestinal/efeitos da radiação , Géis , Radioisótopos de Ouro , Humanos , Ácido Hialurônico/administração & dosagem , Ácido Hialurônico/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Neoplasias da Próstata/psicologia , Lesões por Radiação/fisiopatologia , Lesões por Radiação/prevenção & controle , Lesões por Radiação/psicologia , Dosagem Radioterapêutica , Reto/diagnóstico por imagem , Ultrassonografia , Viscossuplementos/administração & dosagem
9.
Proc West Pharmacol Soc ; 54: 15-20, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22423573

RESUMO

Parkinson's disease (PD) is characterized by malfunction of dopaminergic systems, and the current symptomatic treatment is to replace lost dopamine. For investigating mechanisms of pathogenesis and alternative treatments to compensate lack of dopamine (DA) activity in PD, the 6-hydroxydopamine (6-OHDA)-lesioned rat model of PD has been useful, these animals display apomorphine-induced contralateral rotational behavior, when they are examined after lesion. The purpose of this study was to assess Titania-dopamine (TiO2-DA) complexes implanted on the caudate nucleus for diminishing motor behavior alterations of the 6-OHDA rat model. Rats with 6-OHDA unilateral lesions received TiO2 alone or TiO2-DA implants, and were tested for open field (OF) gross motor crossing and rearing behaviors, and apomorphine-induced rotation (G) behavior. TiO2 complex have no effects on rearing OF and G behaviors, and a significant reducing effect on crossing motor behavior of normal rats compared to control non-treated rats throughout 56 days of observation. Interestingly, TiO2-DA treatment significant recovered motor crossing and rearing behaviors in 6-OHDA-lesioned rats, and diminished the G behaviors during 56 days of examination. Additionally, in the 6-OHDA-lesioned rats TiO2 treatment had a moderate recovering effect only on crossing behavior compared to lesioned non treated rats. Our results suggest that continuous release of dopamine in the caudate nucleus from TiO2-DA complex is capable of reversing gross motor deficits observed in the 6-OHDA-lesioned rat model of PD. Thistype of delivery system of DA represents a promising therapy for PD in humans.


Assuntos
Núcleo Caudado/fisiologia , Dopamina/administração & dosagem , Atividade Motora , Transtornos Parkinsonianos/terapia , Titânio/administração & dosagem , Animais , Apomorfina/farmacologia , Masculino , Transtornos Parkinsonianos/fisiopatologia , Ratos , Ratos Wistar , Rotação
10.
Breast J ; 16(6): 581-6, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21070434

RESUMO

The objective of this study was to report our single-institution results with MammoSite and multi-catheter brachytherapy. Between February 2003 and January 2009, 173 women with unifocal pathological Tis, T1, or T2 (up to 30 mm), N0 or N1 carcinomas of the breast were treated with post-lumpectomy brachytherapy to 34 Gy in 10 fractions over 5-10 days. We treated 137 patients with MammoSite single-lumen balloon brachytherapy, and 36 patients with multi-catheter brachytherapy. Patients with small and/or nonspherical lumpectomy cavities were usually treated with multi-catheter brachytherapy using 4-12 interstitial catheters. Median follow-up was 33 months. Three-year ipsilateral breast tumor control, disease-free, and overall survival rates for MammoSite brachytherapy were 100%, 100%, and 99%, respectively. Similar rates were obtained with multi-catheter brachytherapy. Minimum distances from the planning target volume for plan evaluation to a rib were 10 ± 8 mm (mean ± standard deviation) and 8 ± 4 mm (mean ± standard deviation) for MammoSite brachytherapy and multi-catheter brachytherapy, respectively (p = 0.48). Maximum rib doses were 101 ± 14% (mean ± standard deviation) and 74 ± 10% (mean ± standard deviation) of the prescribed dose for MammoSite brachytherapy and multi-catheter brachytherapy, respectively (p = 0.001). Multi-catheter brachytherapy results in more conformal radiation dose delivery and a significantly lower rib dose than MammoSite single-lumen brachytherapy. Long-term follow-up is needed to determine if the delivery of a lower radiation dose to the ribs will translate into a lower incidence of rib pain and fractures.


Assuntos
Braquiterapia/métodos , Neoplasias da Mama/radioterapia , Mastectomia Segmentar , Adulto , Idoso , Idoso de 80 Anos ou mais , Braquiterapia/efeitos adversos , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias
11.
Int J Radiat Oncol Biol Phys ; 78(3): 799-803, 2010 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-20869583

RESUMO

PURPOSE: To report our results with accelerated partial breast irradiation (APBI) in terms of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER-2/neu) status. METHODS AND MATERIALS: Between February 2003 and June 2009, 209 women with early-stage breast carcinomas were treated with APBI using multicatheter, MammoSite, or Contura brachytherapy to 34 Gy in 10 fractions twice daily over 5-7 days. Three patient groups were defined by receptor status: Group 1: ER or PR (+) and HER-2/neu (-) (n = 180), Group 2: ER and PR (-) and HER-2/neu (+) (n = 10), and Group 3: ER, PR, and HER-2/neu (-) (triple negative breast cancer, n = 19). Median follow-up was 22 months. RESULTS: Group 3 patients had significantly higher Scarff-Bloom-Richardson scores (p < 0.001). The 3-year ipsilateral breast tumor control rates for Groups 1, 2, and 3 were 99%, 100%, and 100%, respectively (p = 0.15). Group 3 patients tended to experience relapse in distant sites earlier than did non-Group 3 patients. The 3-year relapse-free survival rates for Groups 1, 2, and 3 were 100%, 100%, and 81%, respectively (p = 0.046). The 3-year cause-specific and overall survival rates for Groups 1, 2, and 3 were 100%, 100%, and 89%, respectively (p = 0.002). CONCLUSIONS: Triple negative breast cancer patients typically have high-grade tumors with significantly worse relapse-free, cause-specific, and overall survival. Longer follow-up will help to determine whether these patients also have a higher risk of ipsilateral breast tumor relapse.


Assuntos
Neoplasias da Mama/química , Neoplasias da Mama/radioterapia , Proteínas de Neoplasias/análise , Receptor ErbB-2/análise , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Braquiterapia/efeitos adversos , Braquiterapia/métodos , Neoplasias da Mama/etnologia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Distribuição de Qui-Quadrado , Fracionamento da Dose de Radiação , Feminino , Humanos , Mastectomia Segmentar , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/prevenção & controle , Análise de Regressão , Estatísticas não Paramétricas , Taxa de Sobrevida
12.
Int J Radiat Oncol Biol Phys ; 77(3): 824-30, 2010 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-20510195

RESUMO

PURPOSE: To prospectively analyze whether cross-linked hyaluronan gel reduces the mean rectal dose and acute rectal toxicity of radiotherapy for prostate cancer. METHODS AND MATERIALS: Between September 2008 and March 2009, we transperitoneally injected 9 mL of cross-linked hyaluronan gel (Hylaform; Genzyme Corporation, Cambridge, MA) into the anterior perirectal fat of 10 early-stage prostate cancer patients to increase the separation between the prostate and rectum by 8 to 18 mm at the start of radiotherapy. Patients then underwent high-dose rate brachytherapy to 2,200 cGy followed by intensity-modulated radiation therapy to 5,040 cGy. We assessed acute rectal toxicity using the National Cancer Institute Common Terminology Criteria for Adverse Events v3.0 grading scheme. RESULTS: Median follow-up was 3 months. The anteroposterior dimensions of Hylaform at the start and end of radiotherapy were 13 +/- 3mm (mean +/- SD) and 10 +/- 4mm, respectively. At the start of intensity-modulated radiation therapy, daily mean rectal doses were 73 +/- 13 cGy with Hylaform vs. 106 +/- 20 cGy without Hylaform (p = 0.005). There was a 0% incidence of National Cancer Institute Common Terminology Criteria for Adverse Events v3.0 Grade 1, 2, or 3 acute diarrhea in 10 patients who received Hylaform vs. a 29.7% incidence (n = 71) in 239 historical controls who did not receive Hylaform (p = 0.04). CONCLUSIONS: By increasing the separation between the prostate and rectum, Hylaform decreased the mean rectal dose. This led to a significant reduction in the acute rectal toxicity of radiotherapy for prostate cancer.


Assuntos
Materiais Biocompatíveis/administração & dosagem , Braquiterapia/efeitos adversos , Ácido Hialurônico/análogos & derivados , Neoplasias da Próstata/radioterapia , Lesões por Radiação/prevenção & controle , Radioterapia de Intensidade Modulada/efeitos adversos , Reto/efeitos da radiação , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Braquiterapia/métodos , Diarreia/etiologia , Diarreia/prevenção & controle , Humanos , Ácido Hialurônico/administração & dosagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Neoplasias da Próstata/patologia , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos
13.
Brachytherapy ; 9(2): 171-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19854114

RESUMO

PURPOSE: To analyze prognostic factors in adequately staged breast cancer patients who were treated with accelerated partial breast irradiation (APBI). METHODS AND MATERIALS: Axillary staging was required for invasive carcinomas. Between February 2003 and June 2009, 204 women with early stage breast carcinomas were treated with APBI using multicatheter, MammoSite, or Contura brachytherapy to 34 Gy in 10 fractions 2 times per day. Six patient characteristics were examined for prognostic significance: (1) N stage, (2) estrogen receptor (ER) status, (3) histologic subtype, (4) margin status, (5) age, and (6) tumor size. The median followup was 22 months. RESULTS: There were three failures in the ipsilateral breast (all were elsewhere failures), one relapse in the axilla, and seven relapses at any site. The presence of positive axillary node(s) had a significant adverse effect on ipsilateral breast tumor control (p=0.045) and locoregional control (p=0.001). The presence of an ER (-) tumor had a significant adverse effect on relapse-free survival (p=0.04). CONCLUSIONS: The patients with positive axillary node(s) were at increased risk for failure elsewhere in the ipsilateral breast or axilla, and the patients with ER (-) tumors were at increased risk for relapse at any site. However, it is unclear whether the pN1 and ER (-) patients would have faired any better if they had received whole breast irradiation rather than APBI. We believe that the patients with positive axillary node(s) or ER (-) tumors should be treated on clinical trials to better define the role of APBI.


Assuntos
Braquiterapia/métodos , Neoplasias da Mama/radioterapia , Fracionamento da Dose de Radiação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/diagnóstico , Feminino , Humanos , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Fatores de Risco , Resultado do Tratamento , Adulto Jovem
14.
Brachytherapy ; 9(4): 341-8, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19853534

RESUMO

PURPOSE: To analyze results with high-dose-rate (HDR) brachytherapy and intensity modulated radiation therapy (IMRT) vs. IMRT alone for prostate cancer. METHODS AND MATERIALS: Between October 2003 and August 2008, 284 patients with early stage prostate cancer underwent HDR brachytherapy to 2200cGy and IMRT to 5040cGy (n=240) or IMRT alone to 7920-8100cGy (n=44). RESULTS: The median followup was 2.2 years. There was no significant difference in terms of the proportions of patients who had diabetes mellitus (p=0.07) or who received hormonal therapy (p=0.75) by radiotherapy technique. The 3-year biochemical disease-free survival rates in low-risk, intermediate-risk, and high-risk patients treated with HDR brachytherapy and IMRT are 100%, 98%, and 93%, respectively. The 3-year biochemical disease-free survival rates in low-risk, intermediate-risk, and high-risk patients treated with IMRT alone are 100%, 100%, and 67%, respectively. There was no significant difference in biochemical disease-free survival or toxicity between treatment groups. The similarity in outcomes between treatment groups remained unchanged when we examined only hormone-naive patients. CONCLUSIONS: The HDR brachytherapy and IMRT yielded similar biochemical disease-free survival and toxicity to IMRT alone. As a result, we continue to base treatment on physician and patient preference. Longer followup will help to determine the role of HDR brachytherapy and IMRT in the treatment of early stage prostate cancer, particularly because a number of patients received androgen deprivation therapy and we delivered a higher biologically effective dose with combined modality therapy.


Assuntos
Braquiterapia/métodos , Neoplasias da Próstata/radioterapia , Radioterapia de Intensidade Modulada/métodos , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Intervalo Livre de Doença , Ouro , Humanos , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Fatores de Risco
15.
Artigo em Inglês | WHO IRIS | ID: who-170472

RESUMO

Dengue viruses (DENV) are the most important arboviruses of public health significance, and compriseof four distinct antigenic serotypes (DENV-1 to 4) that show substantial genetic diversity. These virusesusually cause dengue fever (DF) but some patients progress to a more severe form of the illness, i.e.dengue haemorrhagic fever/dengue shock syndrome (DHF/DSS). The first reports of DENV-3 cases inBrazil occurred in the year 2000 with co-circulation of DENV-1 and 2. Thereafter, DENV-3 spreadthroughout the country. DENV-3 phylogenetic analysis has revealed the existence of four to five DENV-3 genotypes. Genotype III of DENV-3 has been the main genotype circulating in Brazil, but recent studieshave indicated that DENV-3 genotype I and genotype V are also circulating in some states of Brazil. Inorder to evaluate DENV-3 genotypes circulating in São Paulo state from 2003 through 2008 we analyzedthe NS1 region of DENV-3 isolated from patients residing in Ribeirão Preto and presenting with differentclinical manifestations of dengue disease. Nucleotide sequences from 31 viruses were obtained andcompared to 105 DENV-3 corresponding sequences retrieved from GenBank. Phylogenetic analysisshowed that São Paulo DENV-3 sequences belong to genotype III and that Puerto Rico strains are closelyrelated to South American strains. There was no association between DENV-3 genotype and DHF/DSS.


Assuntos
Vírus da Dengue , Aedes , Filogenia , Brasil , Dengue Grave
16.
J Nanosci Nanotechnol ; 8(12): 6491-6, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19205228

RESUMO

Sol-gel thin films containing Fe2o3 were deposited onto glass substrates by the dip-coating method at room temperature. Fe2O3 enriched with the isotope 57Fe was embedded in two kinds of matrices: zinc oxide (ZnO) and silica (SiO2). X-ray diffraction (XRD) was used for morphology and structure determination of the nanostructures and showed that the ZnO exhibit a wurtzite form when the film is annealed at 450 degrees C for 20 min. SiO2 thin films at C16H33PEO20:Fe2O3 = 1:2.7 x 10(-1) molar concentration exhibit a hexagonal nanophase produced by the diblock copolymer Brij58 (C16H33PEO20). Optical absorption and infrared spectroscopy techniques were used to evaluate the optical quality of the films. In order to determine if the Fe2O3 was incorporated into the matrices, room temperature Mössbauer spectra of both samples were obtained. In both cases the hematite spectrum was obtained, corroborating that the incorporation of the Fe2O3 to the matrices was done without chemical reaction whatsoever.

17.
J Nanosci Nanotechnol ; 8(12): 6569-75, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19205242

RESUMO

We report on the photoconductive response of nanostructured sol-gel films in function of the silver nitrate concentration (ions and colloids). Silver colloids were obtained by spontaneous reduction process of Ag+ ions to Ag(0). 2-d hexagonal nanosructured sol-gel thin films were prepared by dip-coating method using the non-ionic diblock copolymer Brij58 to produce channels into the film, which house the silver nanoparticles. An optical absorption band located at 430 nm was detected by optical absorption; it corresponds to the surface plasmon. A fit to this band with modified Gans theory is presented. Photoconductivity studies were performed on films with silver ions and films with silver colloids to characterize their mechanisms of charge transport in the darkness and under illumination at 420 and 633 nm wavelengths. The films with silver colloids exhibit a photovoltaic effect stronger than the films with silver ions. While a photoconductive behaviour is observed in the films with silver ions.

18.
J Nanosci Nanotechnol ; 8(12): 6576-83, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19205243

RESUMO

Pump-probe photoinduced birefringence measurements were carried out in amorphous and in nanostructured sol-gel films with Disperse Red 1 (DR1) azochromophores embedded in a SiO2 matrix. X-ray diffraction (XRD) patterns determine the long-range nanostructure order of the films, exhibiting a lamellar nanostructure, with two different d-spacings, due to the presence during the sol-gel process of the Sodium Dodecyl Sulfate (SDS) or of the Cetyltrimethylammonium Bromide (CTAB) ionic surfactants. The photoinduced birefringence measurements were performed on fresh and on heat treated films as a function of the pumping time. The measurements give us information about the effect of the nanostructures on the azochromophores orientation dynamics. As a result, for the same azochromophores concentration, annealed nanostructured films exhibited the largest azochromophore mobilities but by the other side, amorphous films had the largest signal intensities. Besides, we established a phenomenological model for the analysis of the azochromophores orientation in the films as a function of the pumping time.

19.
Rev Med Inst Mex Seguro Soc ; 46(2): 205-10, 2008.
Artigo em Espanhol | MEDLINE | ID: mdl-19133194

RESUMO

Pyogenic liver abscess is still considered a medical challenge due to the seriousness of the clinical course, late diagnosis, and usually high mortality. Gas-forming liver abscess is not uncommon, the incidence among all pyogenic liver abscess is around 7 to 24 %, mostly in individuals in their sixth and seventh decades ,and with diabetes mellitus disease. The epidemiology of gas-forming liver abscess has been changing with a shift from young to older diabetic adults. A clinical case of a 71 year old diabetic female with gas-forming liver abscess is presented; we describe the clinical course and treatment is analyzed.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Abscesso Hepático Piogênico/complicações , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Abscesso Hepático Piogênico/diagnóstico , Abscesso Hepático Piogênico/microbiologia , Tomografia Computadorizada por Raios X
20.
Rev Invest Clin ; 59(1): 87-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17569304

RESUMO

Aortic dissection is a cardiovascular emergency. Its main manifestation is severe chest pain, and approximately 50% of patients present with an elevated systemic blood pressure. Rare reported physical findings include a pulsatile sterno-clavicular joint, dysphagia or testicular tenderness. The absence of sudden onset of pain lowers the likelihood of aortic dissection. We describe a patient in whom aortic dissection was accompanied by fever, nightsweats, suprasternal pain and atrial fibrillation.


Assuntos
Aneurisma Aórtico/diagnóstico , Dissecção Aórtica/diagnóstico , Fibrilação Atrial/etiologia , Febre/etiologia , Idoso , Dissecção Aórtica/complicações , Aorta/patologia , Aneurisma Aórtico/complicações , Dor no Peito/etiologia , Eletrocardiografia , Feminino , Humanos , Hiperidrose/etiologia , Hipertensão/complicações , Derrame Pericárdico/etiologia
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