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1.
Chemosphere ; 362: 142456, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38878982

RESUMO

The ecologically friendly properties, low-cost, and readily available titanium dioxide (TiO2) materials have made them a subject of considerable interest for numerous promising applications. Anatase TiO2 nanoparticles were synthesized in the current study through the utilization of a hibiscus leaf extract and the advent of TiO2-doped g-C3N4(TiCN) nanocomposites (varying 0.5 mM, 1.0 mM, 1.5 mM, and 2.0 mM) by thermal polymerization. Here, the proposed study utilized multiple analytical techniques, including UV-Vis spectroscopy, a diffraction pattern (XRD), SEM coupled with EDX analysis, TGA, and EPR, to characterize the as-prepared TiO2 nanoparticles and TiCN nanocomposites. BET analysis the adsorption-desorption isotherms of the TiCN(1.5 mM) nanocomposite, the surface area of the prepared nanocomposite is 112.287 m2/g, and the pore size is 7.056 nm. The XPS spectra support the development of the TiCN(1.5 mM) nanocomposite by demonstrating the presence of C and N elements in the nanocomposite in addition to TiO2. HRTEM images where the formation of stacked that indicates a planar, wrinkled graphitic-like structure is clearly visible. The TiCN (1.5 mM) specimen exhibited enhanced morphology, enhanced surface area, greater capacity to take in visible light, and lowered band gap when compared to g-C3N4 following z-scheme heterojunction. The sample denoted as TiCN (1.5 mM) exhibited superior performance in terms of adsorption and photocatalytic activity using rhodamine B and Bisphenol A. Furthermore, the TiCN (1.5 mM) composite exhibited satisfactory stability over four cyclic runs, indicating its potential application in minimizing the impact of organic wastewater contaminants when compared to g-C3N4.

2.
Beilstein J Org Chem ; 9: 26-35, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23400045

RESUMO

Non-symmetrically substituted four-ring achiral bent-core compounds with polar substituents, i.e.., chloro in the bent or transverse direction in the central core and cyano in the lateral direction at one terminal end of the molecule, are designed and synthesized. These molecules possess an alkoxy chain attached at only one end of the bent-core molecule. The molecular structure characterization is consistent with data from elemental and spectroscopic analysis. The materials thermal behaviour and phase characterization have been investigated by differential scanning calorimetry and polarizing microscopy. All the compounds exhibit a wide-ranging monotropic nematic phase.

3.
J Surg Oncol ; 105(8): 745-9, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22161989

RESUMO

BACKGROUND: Circumferential resection margin (CRM) is widely recognized as an important prognostic factor in esophageal cancer. The aim of this study was to evaluate the clinical significance of CRM according to the current criteria of the Royal College of Pathologists (RCP) and the College of American Pathologists (CAP). METHODS: Patients (115) who underwent esophagectomy between 2000 and 2006 were included in this retrospective study. Factors such as neo-adjuvant therapy, site, histological type, size, and lymph node involvement were tested to determine predictability of CRM involvement. Along with these, age, sex, CRM, and adjuvant therapy were analyzed to determine influence on survival. RESULTS: On the basis of CRM, patients were divided into three groups (involved, 0.1-1 mm and >1mm). Size (T) was the only factor strongly predictive of CRM involvement (P < 0.001). Size (T; P = 0.04) and lymph node involvement (N; P = 0.0003) were found to significantly influence overall survival (OS). When patients with CRM (involved and 0.1-1mm) were compared with those with CRM > 1 mm, OS was significantly prolonged in the latter (P = 0.02). CONCLUSION: This study appears to lend credence to the RCP criteria for definition of CRM over the CAP criteria.


Assuntos
Adenocarcinoma/cirurgia , Carcinoma de Células Escamosas/cirurgia , Neoplasias Esofágicas/cirurgia , Esofagectomia/mortalidade , Linfonodos/patologia , Linfonodos/cirurgia , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
5.
ACS Appl Mater Interfaces ; 14(37): 42628-42634, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36082439

RESUMO

In this study, we used a new series of highly polar three-ring-based bent-core liquid crystals (BCLCs) to stabilize a wide temperature range of blue phase III (BPIII), including room temperature. A significant finding is the implementation of electro-optical (E-O) switching at room temperature in the current BPIII system. The observed Kerr constant (K) has an extraordinarily high value (K ≈ 9.2 × 10-9m V-2) that exceeds all previously reported values in the category of BPIII materials. The extremely high value of K realizes the lowest operating voltage (Von ≈ 3.3 Vrms/µm) for BPIII. The measured values of K and Von in BPIII set a new limit for the experimentalist. The millisecond (ms) order response times are explained based on rotational viscosity. The present binary system of BPIII materials is an excellent choice for device application.

6.
Braz J Med Biol Res ; 54(10): e11391, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34406209

RESUMO

Nonalcoholic fatty liver disease (NAFLD), characterized by hepatosteatosis and steatohepatitis, is intrinsically related to obesity. Our previous study reported on the anti-obese activity of α,ß-amyrin (AMY), a pentacyclic triterpene isolated from Protium heptaphyllum. This study investigated its ability to prevent fatty liver and the underlying mechanism using the mouse model of NAFLD. NAFLD was induced in male Swiss mice fed a high fat diet (HFD) for 15 weeks. The controls were fed a normal chow diet (ND). The mice were simultaneously treated with AMY at 10 and 20 mg/kg or fenofibrate at 50 mg/kg. Lipid levels along with metabolic and inflammatory parameters were assessed in liver and serum. The liver sections were histologically examined using H&E staining. RT-qPCR and western blotting assays were performed to analyze signaling mechanisms. Mice fed HFD developed severe hepatic steatosis with elevated triglycerides and lipid droplets compared with ND controls. This was associated with a decrease in AMP-activated protein kinase (AMPK) activity, an increase of mechanistic target of rapamycin complex 1 (mTORC1) signaling, and enhanced sterol regulatory element binding protein 1 (SREBP1) expression, which have roles in lipogenesis, inhibition of lipolysis, and inflammatory response. AMY treatment reversed these signaling activities and decreased the severity of hepatic steatosis and inflammatory response, evidenced by serum and liver parameters as well as histological findings. AMY-induced reduction in hepatic steatosis seemed to involve AMPK-mTORC1-SREBP1 signaling pathways, which supported its beneficial role in the prevention and treatment of NAFLD.


Assuntos
Resistência à Insulina , Hepatopatia Gordurosa não Alcoólica , Proteínas Quinases Ativadas por AMP , Animais , Dieta Hiperlipídica/efeitos adversos , Fígado , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Ácido Oleanólico/análogos & derivados , Proteína de Ligação a Elemento Regulador de Esterol 1
7.
Mutat Res ; 701(2): 153-63, 2010 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-20599626

RESUMO

Kaurane diterpenes are considered important compounds in the development of new highly effective anticancer chemotherapeutic agents. Genotoxic effects of anticancer drugs in non-tumour cells are of special significance due to the possibility that they induce secondary tumours in cancer patients. In this context, we evaluated the genotoxic and mutagenic potential of the natural diterpenoid kaurenoic acid (KA), i.e. (-)-kaur-16-en-19-oic acid, isolated from Xylopia sericeae St. Hill, using several standard in vitro and in vivo protocols (comet, chromosomal aberration, micronucleus and Saccharomyces cerevisiae assays). Also, an analysis of structure-activity relationships was performed with two natural diterpenoid compounds, 14-hydroxy-kaurane (1) and xylopic acid (2), isolated from X. sericeae, and three semi-synthetic derivatives of KA (3-5). In addition, considering the importance of the exocyclic double bond (C16) moiety as an active pharmacophore of KA cytotoxicity, we also evaluated the hydrogenated derivative of KA, (-)-kauran-19-oic acid (KAH), to determine the role of the exocyclic bond (C16) in the genotoxic activity of KA. In summary, the present study shows that KA is genotoxic and mutagenic in human peripheral blood leukocytes (PBLs), yeast (S. cerevisiae) and mice (bone marrow, liver and kidney) probably due to the generation of DNA double-strand breaks (DSB) and/or inhibition of topoisomerase I. Unlike KA, compounds 1-5 and KAH are completely devoid of genotoxic and mutagenic effects under the experimental conditions used in this study, suggesting that the exocyclic double bond (C16) moiety may be the active pharmacophore of the genetic toxicity of KA.


Assuntos
Diterpenos/química , Diterpenos/toxicidade , Mutagênicos/toxicidade , Extratos Vegetais/toxicidade , Animais , Linhagem Celular Tumoral , Humanos , Masculino , Camundongos , Testes de Mutagenicidade , Relação Estrutura-Atividade
8.
Radiat Res ; 169(3): 319-29, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18302487

RESUMO

Intracellular Ca(2+) spikes trigger cell proliferation, differentiation and cytoskeletal reorganization. In addition to Ca(2+) spiking that can be initiated by a ligand binding to its receptor, exposure to electromagnetic stimuli has also been shown to alter Ca(2+) dynamics. Using neuronal cells differentiated from a mouse embryonic stem cell line and a custom-built, frequency-tunable applicator, we examined in real time the altered Ca(2+) dynamics and observed increases in the cytosolic Ca(2+) in response to nonthermal radiofrequency (RF)-radiation exposure of cells from 700 to 1100 MHz. While about 60% of control cells (not exposed to RF radiation) were observed to exhibit about five spontaneous Ca(2+) spikes per cell in 60 min, exposure of cells to an 800 MHz, 0.5 W/kg RF radiation, for example, significantly increased the number of Ca(2+) spikes to 15.7+/-0.8 (P<0.05). The increase in the Ca(2+) spiking activities was dependent on the frequency but not on the SAR between 0.5 to 5 W/kg. Using pharmacological agents, it was found that both the N-type Ca(2+) channels and phospholipase C enzymes appear to be involved in mediating increased Ca(2+) spiking. Interestingly, microfilament disruption also prevented the Ca(2+) spikes. Regulation of Ca(2+) dynamics by external physical stimulation such as RF radiation may provide a noninvasive and useful tool for modulating the Ca(2+)-dependent cellular and molecular activities of cells seeded in a 3D environment for which only a few techniques are currently available to influence the cells.


Assuntos
Sinalização do Cálcio/fisiologia , Sinalização do Cálcio/efeitos da radiação , Cálcio/metabolismo , Neurônios/citologia , Neurônios/fisiologia , Células-Tronco/citologia , Células-Tronco/fisiologia , Animais , Canais de Cálcio Tipo L/fisiologia , Canais de Cálcio Tipo L/efeitos da radiação , Diferenciação Celular/efeitos da radiação , Proliferação de Células/efeitos da radiação , Células Cultivadas , Relação Dose-Resposta à Radiação , Temperatura Alta , Taxa de Depuração Metabólica/efeitos da radiação , Camundongos , Neurônios/efeitos da radiação , Doses de Radiação , Ondas de Rádio , Células-Tronco/efeitos da radiação
9.
Bioorg Med Chem Lett ; 18(23): 6054-7, 2008 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-18948000

RESUMO

A series of N-2-(4-(4-(2-substitutedthiazol-4-yl) piperazin-1-yl)-2-oxoethyl)acetamides were synthesized in an effort to prepare novel atypical antipsychotic agents. The compounds were synthesized by either microwave irradiation technique or by conventional synthesis and were characterized by spectral data (IR, (1)H NMR, and MS) and the purity was ascertained by microanalysis. All the synthesized compounds were screened for their in vivo pharmacological activity in Swiss albino mice. D(2) antagonism studies were performed using climbing mouse assay model and 5-HT(2A) antagonism studies were performed using quipazine induced head twitches in mice. It was observed that none of the new chemical entities exhibited catalepsy. AG 3 was found to be the most active compound.


Assuntos
Acetamidas/síntese química , Acetamidas/farmacologia , Antipsicóticos/síntese química , Antipsicóticos/farmacologia , Piperazinas/síntese química , Piperazinas/farmacologia , Antagonistas do Receptor 5-HT2 de Serotonina , Acetamidas/química , Animais , Antipsicóticos/química , Técnicas de Química Combinatória , Modelos Animais de Doenças , Movimentos da Cabeça/efeitos dos fármacos , Camundongos , Estrutura Molecular , Atividade Motora/efeitos dos fármacos , Piperazinas/isolamento & purificação , Quipazina/farmacologia
10.
Vasc Health Risk Manag ; 4(1): 199-211, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18629375

RESUMO

The increasing pressure on health resources has led to the emergence of risk assessment as an essential tool in the management of cardiovascular disease (CVD). Concern exists regarding the validity of their generalization to all populations. Existing risk scoring models do not incorporate emerging 'novel' risk factors. In this context, the aim of the study was to examine the relevance of British, European, and Framingham predictive CVD risk scores to the asymptomatic high risk Indian population. Blood samples drawn from the participants were analyzed for various 'traditional' and 'novel' biomarkers, and their CVD risk factor profiling was also done. The Framingham model defined only 5% of the study cohort to be at high risk, which appears to be an underestimation of CVD risk in this genetically predisposed population. These subjects at high risk had significantly elevated levels of lipid, pro-inflammatory, pro-thrombotic, and serological markers. It is more relevant to develop risk predictive scores for application to the Indian population. This study substantiates the argument that alternative approaches to risk stratification are required in order to make them more adaptable and applicable to different populations with varying risk factor and disease patterns.


Assuntos
Biomarcadores/sangue , Doenças Cardiovasculares/epidemiologia , Análise de Variância , Povo Asiático , Índice de Massa Corporal , Doenças Cardiovasculares/sangue , Distribuição de Qui-Quadrado , Feminino , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Medição de Risco , Fatores de Risco
11.
J Clin Invest ; 101(1): 188-94, 1998 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-9421481

RESUMO

The renin-angiotensin system plays a major role in regulating blood pressure and maintaining electrolyte and volume homeostasis. Previously, the angiotensinogen gene, which encodes the key substrate for renin within this system, has been reported linked to and associated with essential hypertension in White Europeans, African-Caribbeans, and Japanese. Therefore, we investigated whether the angiotensinogen gene might be similarly implicated in the pathogenesis of essential hypertension in Chinese by carrying out linkage analysis in 310 hypertensive sibling pairs. Genotypes for two diallelic DNA polymorphisms observed at amino acid residues 174 (T174M) and 235 (M235T) within the coding sequence and for two highly informative dinucleotide (GT)-repeat sequences (one in the 3' flanking region, and one at a distance of 6.1 cM from the gene) were determined. Affected sibpair analysis conducted according to three different algorithms (S.A.G.E./SIBPAL, MAPMAKER/ SIBS, and APM methods) revealed no evidence for linkage of the angiotensinogen gene to hypertension. Our data indicate that molecular variants of this gene do not appear to contribute materially to the pathogenesis of primary hypertension among Chinese (a notion supported by concomitant, direct estimates of power), and that the disease relevance of this gene may vary therefore depending on ethnicity.


Assuntos
Angiotensinogênio/genética , Povo Asiático/genética , Hipertensão/genética , Alelos , Feminino , Ligação Genética , Marcadores Genéticos , Humanos , Hipertensão/metabolismo , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético
13.
Micron ; 38(8): 804-18, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17669661

RESUMO

Nanotechnology has already started to significantly impact many industries and scientific fields including biotechnology, pharmaceutics, food technology and semiconductors. Nanotechnology-based tools and devices, including high-resolution imaging techniques, enable characterization and manipulation of materials at the nanolevel and further elucidate nanoscale phenomena and equip us with the ability to fabricate novel materials and structures. One of the most promising impacts of nanotechnology is in the area of nanotherapy. Employing nanosystems such as dendrimers, nanoliposomes, niosomes, nanotubes, emulsions and quantum dots, nanotherapy leads toward the concept of personalized medicine and the potential for early diagnoses coupled with efficient targeted therapy. The development of smart targeted nanocarriers that can deliver bioactives at a controlled rate directly to the designated cells and tissues will provide better efficacy and reduced side effects. Nanocarriers improve the solubility of bioactives and allow for the delivery of not only small-molecule drugs but also the delivery of nucleic acids and proteins. This review will focus on nanoscale bioactive delivery and targeting mechanisms and the role of high-resolution imaging techniques in the evaluation and development of nanocarriers.


Assuntos
Portadores de Fármacos , Terapia Genética/métodos , Nanopartículas/ultraestrutura , DNA/administração & dosagem , Dendrímeros , Lipossomos , Microscopia de Força Atômica , Microscopia de Tunelamento
14.
Micron ; 38(8): 841-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17689087

RESUMO

Nanoencapsulation may improve activity of protein or polypeptide antimicrobials against a variety of microorganisms. In this study, nanoliposomes prepared from different lipids (Phospholipon 90H, Phospholipon 100H, dipalmitoylphosphatidylcholine (DPPC), stearylamine (SA), dicetyl phosphate (DCP) and cholesterol) by a new, non-toxic and scalable method, were tested for their capacity to encapsulate nisin Z and target bacteria (Bacillus subtilis and Pseudomonasaeruginosa). Factors affecting the entrapment efficiency (charge and cholesterol concentration in the vesicles) and stability of nanoliposomes were assessed. The nanoliposomes and their bacterial targeting were visualised, using different microscopes under air and liquid environments. Nisin was entrapped in different nanoliposomes with encapsulation efficiencies (EE) ranging from 12% to 54%. Anionic vesicles possessed the highest EE for nisin while increase in cholesterol content in lipid membranes up to 20% molar ratio resulted in a reduction in EE. Stability of nanoliposome-encapsulated nisin was demonstrated for at least 14 months at 4 degrees C (DPPC:DCP:CHOL vesicles) and for 12 months at 25 degrees C (DPPC:SA:CHOL vesicles).


Assuntos
Antibacterianos/administração & dosagem , Bactérias/efeitos dos fármacos , Lipossomos , Nanopartículas/ultraestrutura , Nisina/administração & dosagem , Androstanos , Microscopia de Força Atômica , Tamanho da Partícula , Tecnologia Farmacêutica
15.
Braz J Med Biol Res ; 40(3): 349-56, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17334532

RESUMO

Dental caries and periodontal disease are associated with oral pathogens. Several plant derivatives have been evaluated with respect to their antimicrobial effects against such pathogenic microorganisms. Lippia sidoides Cham (Verbenaceae), popularly known as "Alecrim-pimenta" is a typical shrub commonly found in the Northeast of Brazil. Many plant species belonging to the genus Lippia yield very fragrant essential oils of potential economic value which are used by the industry for the commercial production of perfumes, creams, lotions, and deodorants. Since the leaves of L. sidoides are also extensively used in popular medicine for the treatment of skin wounds and cuts, the objective of the present study was to evaluate the composition and antimicrobial activity of L. sidoides essential oil. The essential oil was obtained by hydro-distillation and analyzed by GC-MS. Twelve compounds were characterized, having as major constituents thymol (56.7%) and carvacrol (16.7%). The antimicrobial activity of the oil and the major components was tested against cariogenic bacterial species of the genus Streptococcus as well as Candida albicans using the broth dilution and disk diffusion assays. The essential oil and its major components thymol and carvacrol exhibited potent antimicrobial activity against the organisms tested with minimum inhibitory concentrations ranging from 0.625 to 10.0 mg/mL. The most sensitive microorganisms were C. albicans and Streptococcus mutans. The essential oil of L. sidoides and its major components exert promising antimicrobial effects against oral pathogens and suggest its likely usefulness to combat oral microbial growth.


Assuntos
Anti-Infecciosos/farmacologia , Candida albicans/efeitos dos fármacos , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Streptococcus/efeitos dos fármacos , Cimenos , Avaliação Pré-Clínica de Medicamentos , Cromatografia Gasosa-Espectrometria de Massas , Lippia/química , Testes de Sensibilidade Microbiana , Monoterpenos/química , Óleos Voláteis/isolamento & purificação , Óleos de Plantas/isolamento & purificação , Timol/química
16.
J Ethnopharmacol ; 113(3): 471-8, 2007 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-17714897

RESUMO

In Brazilian folk medicine, Lippia sidoides (Ls) and Myracrodruon urundeuva (Mu) have gained popularity and reputation as effective antimicrobial and anti-inflammatory agents. This work aimed to evaluate the effect of topical herbal gel from Ls 0.5% (v/w) and Mu 5% (w/w) in experimental periodontal disease (EPD) in rats. Wistar rats were subjected to ligature placement around the second upper left molars. Animals were treated topically with Ls and/or Mu-based gel, immediately after EPD induction and three times/day for 11 days until the rats were sacrificed (11th day). Saline-based gel was utilized as control for all experiments and doxycycline based gel 10% (w/w) was utilized as reference substance. Animals were weighed daily. Alveolar bone loss was measured as the difference (in millimeters) between the cusp tip and the alveolar bone. The periodontum and the surrounding gingivae were examined at histopathology, as well as the neutrophil influx into the gingivae was assayed using myeloperoxidase activity and cytokine production mainly tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) levels by ELISA method. The local bacterial flora was assessed through culture of the gingival tissue in standard aerobic and anaerobic media. Alveolar bone loss was significantly inhibited by Ls and Mu combined treatment compared to the saline control group. Ls and Mu combined treatment reduced tissue lesion at histopathology, with partial preservation of the periodontum, coupled to decreased myeloperoxidase activity as well as significantly inhibited TNF-alpha and IL-1beta production in gingival tissue compared to the saline control group. Ls and Mu combined treatment also prevented the growth of oral microorganisms and the weight loss. Ls and Mu combined based gel treatment preserved alveolar bone resorption and demonstrated anti-inflammatory and antibacterial activities in experimental periodontitis.


Assuntos
Perda do Osso Alveolar/tratamento farmacológico , Anacardiaceae/química , Lippia/química , Periodontite/tratamento farmacológico , Óleos de Plantas/uso terapêutico , Perda do Osso Alveolar/imunologia , Perda do Osso Alveolar/patologia , Animais , Candida albicans/efeitos dos fármacos , Candida albicans/isolamento & purificação , Géis/uso terapêutico , Gengiva/efeitos dos fármacos , Gengiva/imunologia , Gengiva/microbiologia , Interleucina-1beta/imunologia , Masculino , Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Periodontite/imunologia , Periodontite/patologia , Peroxidase/imunologia , Extratos Vegetais/uso terapêutico , Ratos , Ratos Wistar , Streptococcus/efeitos dos fármacos , Streptococcus/isolamento & purificação , Fator de Necrose Tumoral alfa/imunologia
17.
Surgeon ; 5(4): 199-201, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17849953

RESUMO

INTRODUCTION: Stapled techniques of coloanal anastomosis in anterior resection have gained widespread acceptance over hand anastomosis. We believe a modification of the 'triple staple technique' has ergonomic advantages over existing stapling methods and present our technique and experience here. METHODS: Fifty consecutive patients underwent anterior resection with a concomitant defunctioning ileostomy in 44 (86%) patients. A modified triple staple technique of side to end coloanal anastomosis was performed without the need of a purse string suture on the proximal and the distal segments. RESULTS: There were no major intra-operative complications. 2/50 (4%) clinical leaks and 2/37 (5.4%) radiological leaks were noted. A combined leak rate of 4/50 (8%) was reported. The incidence of anastomotic stricture encountered was 1/50 (2%). CONCLUSION: The modified triple staple technique for side to end anastomosis in anterior resection has ergonomic advantages and comparable safety to the existing techniques of stapling coloanal anastomosis. We believe this technique can be widely adopted as an added alternative to the current techniques of stapled anastomosis after anterior resection.


Assuntos
Colo/cirurgia , Doenças do Colo/cirurgia , Reto/cirurgia , Técnicas de Sutura/instrumentação , Anastomose Cirúrgica/métodos , Colectomia/métodos , Humanos , Resultado do Tratamento
18.
ISA Trans ; 46(1): 59-71, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17240376

RESUMO

A simple method of designing the controllers for a modified form of Smith predictor is proposed for integrating and double integrating processes with time delay. The modified Smith predictor has two controllers, namely, a set point tracking controller and a load disturbance rejection controller for obtaining good set point tracking and load disturbance rejection, respectively. The set point tracking controller is designed using the classical direct synthesis method based on the process model without considering the time delay. The disturbance rejection controller is considered as a proportional-derivative (PD) controller and is designed using optimal gain and phase margin approaches. Set point weighting is considered for reducing undesirable overshoots and settling times in the modified Smith predictor. Guidelines are provided for selection of the desired closed loop tuning parameter in the direct synthesis method and the set point weighting parameter. The method gives significant load disturbance rejection performances. Illustrative examples are considered to show the performances of the proposed method. A significant improvement in control performance is obtained when compared to recently reported methods.

19.
Braz J Med Biol Res ; 50(1): e5630, 2017 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-28076453

RESUMO

Previous studies have reported on the glucose and lipid-lowering effects of ferulic acid (FA) but its anti-obesity potential has not yet been firmly established. This study investigated the possible anti-obesitogenic effects of FA in mice fed a high-fat diet (HFD) for 15 weeks. To assess the antiobesity potential of FA, 32 male Swiss mice, weighing 20-25 g (n=6-8 per group) were fed a normal diet (ND) or HFD, treated orally or not with either FA (10 mg/kg) or sibutramine (10 mg/kg) for 15 weeks and at the end of this period, the body weights of animals, visceral fat accumulation, plasma levels of glucose and insulin hormone, amylase and lipase activities, the satiety hormones ghrelin and leptin, and tumor necrosis factor-α (TNF-α) and monocyte chemoattractant protein-1 (MCH-1) were analyzed. Results revealed that FA could effectively suppress the HFD-associated increase in visceral fat accumulation, adipocyte size and body weight gain, similar to sibutramine, the positive control. FA also significantly (P<0.05) decreased the HFD-induced elevations in serum lipid profiles, amylase and lipase activities, and the levels of blood glucose and insulin hormone. The markedly elevated leptin and decreased ghrelin levels seen in HFD-fed control mice were significantly (P<0.05) reversed by FA treatment, almost reaching the values seen in ND-fed mice. Furthermore, FA demonstrated significant (P<0.05) inhibition of serum levels of inflammatory mediators TNF-α, and MCH-1. These results suggest that FA could be beneficial in lowering the risk of HFD-induced obesity via modulation of enzymatic, hormonal and inflammatory responses.


Assuntos
Fármacos Antiobesidade/farmacologia , Ácidos Cumáricos/farmacologia , Ciclobutanos/farmacologia , Gordura Intra-Abdominal/efeitos dos fármacos , Obesidade/tratamento farmacológico , Tecido Adiposo/patologia , Animais , Dieta Hiperlipídica , Modelos Animais de Doenças , Masculino , Camundongos , Obesidade/patologia
20.
Oncol Rep ; 15(1): 179-85, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16328053

RESUMO

Cytokines are known to have both stimulatory and inhibitory effects on breast cancer growth depending on their relative concentrations and the presence of other modulating factors in the tumour microenvironment. Certain cytokines appear to prevent an effective immune response being mounted, permitting cancer growth, whereas others promote the immune system's anti-tumour capability. Furthermore, the systemic levels of certain cytokines, e.g. IL-6 and IL-18, independently show promising correlations with disease stage and progression. With advances in methods for delivery of cytokines to a tumour site, the enhanced induction of anti-tumour immunity by targeted cytokine release is becoming a realistic option. Here, we review the role of cytokines in the immune response against breast cancer and assess their potential as prognostic indicators and/or use in immune therapy. A literature search was conducted using Medline, restricted to articles published in the English language, using combinations of the following MeSH terms: cytokines, breast cancer, immunology, immunotherapy and interleukins. Focused searches using keywords relevant to the role of cytokines in breast cancer immunology yielded >200 references.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/tratamento farmacológico , Citocinas/análise , Citocinas/uso terapêutico , Biomarcadores Tumorais/análise , Neoplasias da Mama/imunologia , Feminino , Humanos , Prognóstico
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