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1.
Molecules ; 26(16)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34443484

RESUMO

The COVID-19 outbreak has rapidly spread on a global scale, affecting the economy and public health systems throughout the world. In recent years, peptide-based therapeutics have been widely studied and developed to treat infectious diseases, including viral infections. Herein, the antiviral effects of the lysine linked dimer des-Cys11, Lys12,Lys13-(pBthTX-I)2K ((pBthTX-I)2K)) and derivatives against SARS-CoV-2 are reported. The lead peptide (pBthTX-I)2K and derivatives showed attractive inhibitory activities against SARS-CoV-2 (EC50 = 28-65 µM) and mostly low cytotoxic effect (CC50 > 100 µM). To shed light on the mechanism of action underlying the peptides' antiviral activity, the Main Protease (Mpro) and Papain-Like protease (PLpro) inhibitory activities of the peptides were assessed. The synthetic peptides showed PLpro inhibition potencies (IC50s = 1.0-3.5 µM) and binding affinities (Kd = 0.9-7 µM) at the low micromolar range but poor inhibitory activity against Mpro (IC50 > 10 µM). The modeled binding mode of a representative peptide of the series indicated that the compound blocked the entry of the PLpro substrate toward the protease catalytic cleft. Our findings indicated that non-toxic dimeric peptides derived from the Bothropstoxin-I have attractive cellular and enzymatic inhibitory activities, thereby suggesting that they are promising prototypes for the discovery and development of new drugs against SARS-CoV-2 infection.


Assuntos
Venenos de Crotalídeos/química , Dimerização , Papaína/antagonistas & inibidores , Peptídeos/química , Peptídeos/farmacologia , SARS-CoV-2/enzimologia , Antivirais/química , Antivirais/metabolismo , Antivirais/farmacologia , Simulação de Acoplamento Molecular , Papaína/química , Papaína/metabolismo , Peptídeos/metabolismo , Inibidores de Proteases/química , Inibidores de Proteases/metabolismo , Inibidores de Proteases/farmacologia , Conformação Proteica , SARS-CoV-2/efeitos dos fármacos
2.
Environ Pollut ; 289: 117818, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34333265

RESUMO

Knowledge about how the COVID-19 pandemic can affect aquatic wildlife is still extremely limited, and no effect of SARS-CoV-2 or its structural constituents on invertebrate models has been reported so far. Thus, we investigated the presence of the 2019-new coronavirus in different urban wastewater samples and, later, evaluated the behavioral and biochemical effects of the exposure of Culex quinquefasciatus larvae to two SARS-CoV-2 spike protein peptides (PSPD-2002 and PSPD-2003) synthesized in our laboratory. Initially, our results show the contamination of wastewater by the new coronavirus, via RT-qPCR on the viral N1 gene. On the other hand, our study shows that short-term exposure (48 h) to a low concentration (40 µg/L) of the synthesized peptides induced changes in the locomotor and the olfactory-driven behavior of the C. quinquefascitus larvae, which were associated with increased production of ROS and AChE activity (cholinesterase effect). To our knowledge, this is the first study that reports the indirect effects of the COVID-19 pandemic on the larval phase of a freshwater invertebrate species. The results raise concerns at the ecological level where the observed biological effects may lead to drastic consequences.


Assuntos
COVID-19 , Culicidae , Animais , Biota , Humanos , Larva , Pandemias , Peptídeos , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus
3.
J Hazard Mater ; 419: 126463, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34216962

RESUMO

The Spike protein (S protein) is a critical component in the infection of the new coronavirus (SARS-CoV-2). The objective of this work was to evaluate whether peptides from S protein could cause negative impact in the aquatic animals. The aquatic toxicity of SARS-CoV-2 Spike protein peptides derivatives has been evaluated in tadpoles (n = 50 tadpoles/5 replicates of 10 animals) from species Physalaemus cuvieri (Leptodactylidae). After synthesis, purification, and characterization of peptides (PSDP2001, PSDP2002, PSDP2003) an aquatic contamination has been simulated with these peptides during 24 h of exposure in two concentrations (100 and 500 ng/mL). The control group ("C") was composed of tadpoles kept in polyethylene containers containing de-chlorinated water. Oxidative stress, antioxidant biomarkers and AChE activity were assessed. In both concentrations, PSPD2002 and PSPD2003 increased catalase and superoxide dismutase antioxidants enzymes activities, as well as oxidative stress (nitrite levels, hydrogen peroxide and reactive oxygen species). All three peptides also increased acetylcholinesterase activity in the highest concentration. These peptides showed molecular interactions in silico with acetylcholinesterase and antioxidant enzymes. Aquatic particle contamination of SARS-CoV-2 has cholinesterasic effect in P. cuvieri tadpoles. These findings indicate that the COVID-19 can constitute environmental impact or biological damage potential.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Anuros , Humanos , Larva , Glicoproteína da Espícula de Coronavírus
4.
Neurourol Urodyn ; 40(1): 538-548, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33326648

RESUMO

AIMS: This study aims to investigate the efficacy of transcutaneous tibial nerve home stimulation for overactive bladder (OAB) in women with Parkinson's disease (PD). METHODS: The current study is a prospective, randomized, double-blind, sham-controlled trial. Home intervention was carried out and assessments were conducted at a tertiary hospital in South Brazil. Women with PD and OAB symptoms were included in the study. Patients were randomly divided into two groups: (1) stimulation and (2) sham. Both groups underwent intervention at home for 12 weeks. Patients were evaluated at baseline and at 12 weeks (end of intervention), 30- and 90-day follow-up. The primary outcome was the mean reduction in the number of urgency incontinence episodes, and secondary outcomes included daytime and nighttime urinary frequency, urinary urgency episodes, use of pad (reported in a 24-h bladder diary), OAB-V8 and King's Health Questionnaire scores, and maintenance of symptom relief after discontinuation of the intervention. RESULTS: In total, 30 consecutive patients completed the study (15/group). The stimulation group showed a reduction in nighttime urinary frequency (0.9 ± 0.6), urinary urgency (1.0 ± 1.2), urgency incontinence episodes (0.5 ± 0.6), use of pads (1.3 ± 1.2), and OAB-V8 (1.3 ± 1.2) and King's Health Questionnaire scores. In a 30-day and 90-day follow-up, 8 (53.3%) and 5 (33.3%) stimulation patients, respectively, reported full maintenance of symptom relief after discontinuation of the intervention. Stimulation patients presented a statistically significant improvement of symptoms as compared with sham patients (p = .001). CONCLUSIONS: Transcutaneous tibial nerve home stimulation can be used in clinical practice as an effective nonpharmacological resource for the reduction of OAB symptoms in women with PD, and the resulting relief seems to persist in the follow-up (30 and 90 days).


Assuntos
Doença de Parkinson/complicações , Nervo Tibial/cirurgia , Estimulação Elétrica Nervosa Transcutânea/métodos , Bexiga Urinária Hiperativa/terapia , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
5.
Anticancer Res ; 40(9): 5151-5158, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32878803

RESUMO

BACKGROUND/AIM: Magnetic stimulation is used in the treatment of a diversity of diseases, but a complete understanding of the underlying mechanisms of action requires further investigation. We examined the effect of static magnetic stimulation (SMS) in different cell lines. MATERIALS AND METHODS: A culture plate holder with attached NeFeB magnets was developed. Different magnetic field intensities and periods were tested in tumoral and non-tumoral cell lines. To verify the cellular responses to SMS, cell viability, cell death, cell cycle and BDNF expression were evaluated. RESULTS: Exposure of SH-SY5Y cells to SMS for 24 hours led to a decrease in cell viability. Analysis 24 h after stimulation revealed a decrease in apoptotic and double-positive cells, associated with an increase in the number of necrotic cells. CONCLUSION: The effects of SMS on cell viability are cell type-specific, inducing a decrease in cell viability in SH-SY5Y cells. This suggests that SMS may be a potential tool in the treatment of neuronal tumors.


Assuntos
Sobrevivência Celular/efeitos da radiação , Fenômenos Magnéticos , Apoptose/efeitos da radiação , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Ciclo Celular/efeitos da radiação , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Humanos , Neuroblastoma/genética , Neuroblastoma/metabolismo , Especificidade de Órgãos/efeitos da radiação
6.
Eur J Obstet Gynecol Reprod Biol ; 250: 203-208, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32464435

RESUMO

OBJECTIVE: To compare the effects of parasacral transcutaneous electrical stimulation with the effects of transcutaneous posterior tibial nerve stimulation in women with overactive bladder syndrome (OAB). STUDYDESIGN: A randomized clinical trial was performed with 50 women aged 40-76 years with symptoms of OAB, divided into two groups: the parasacral transcutaneous electrical stimulation (PS) group and the transcutaneous posterior tibial nerve stimulation (PTN) group. Both groups underwent the same protocol, at home, for 6 weeks, applying electrical stimulation three times per week. The tools used for evaluation were the King's Health Questionnaire (KHQ), the Overactive Bladder-Validated 8-question Awareness Tool (OAB-V8) and the Incontinence Severity Index (ISI). Statistical analysis was undertaken using independent t-test, Mann-Whitney test, Chi-squared test and generalized estimating equations. RESULTS: After 6 weeks of treatment, OAB-V8 showed a significant improvement in the PTN group compared with the PS group (Mann-Whitney test, p = 0.019). Post-intervention, no between-group differences were seen in terms of KHQ domains, average KHQ symptom scale and proportions of categories of ISI. All variables showed a significant effect of time after 6 weeks of treatment for both groups (p < 0.005). CONCLUSION: Both forms of transcutaneous electrical stimulation seem to be effective and safe for home treatment of women with OAB.


Assuntos
Estimulação Elétrica Nervosa Transcutânea , Bexiga Urinária Hiperativa , Incontinência Urinária , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Nervo Tibial , Resultado do Tratamento , Bexiga Urinária Hiperativa/terapia
7.
J Pain ; 21(1-2): 212-224, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31356985

RESUMO

This randomized, double-blind controlled trial tested the hypothesis that 60 sessions of home-based anodal (a)-transcranial direct current stimulation (tDCS) over dorsolateral prefrontal cortex (DLPFC) would be better than home-based sham-tDCS to improve the widespread pain and the disability-related to pain. The anodal-tDCS (2 mA for 30 minutes) over the left DLPFC was self-administered with a specially developed device following in-person training. Twenty women, 18 to 65 years old were randomized into 2 groups [active-(a)-tDCS (n = 10) or sham-(s)-tDCS (n = 10)]. Post hoc analysis revealed that after the first 20 sessions of a-tDCS, the cumulative pain scores reduced by 45.65% [7.25 (1.43) vs 3.94 (1.14), active vs sham tDCS, respectively]. After 60 sessions, during the 12-week assessment, pain scores reduced by 62.06% in the actively group [visual analogue scale reduction, 7.25 (1.43) to 2.75 (.85)] compared to 24.92% in the s-tDCS group, [mean (SD) 7.10 (1.81) vs 5.33 (.90)], respectively. It reduced the risk for analgesic use in 55%. Higher serum levels of the brain-derived neurotrophic factor predicted higher decreases on the pain scores across of treatment. PERSPECTIVE: These findings bring 3 important insights: 1) show that an extended period of treatment (60 sessions, to date the largest number of tDCS sessions tested) for fibromyalgia induces large pain decreases (a large effect size of 1.59) and 2) support the feasibility of home-based tDCS as a method of intervention; 3) provide additional data on DLPFC target for the treatment of fibromyalgia. Finally, our findings also highlight that brain-derived neurotrophic factor to index neuroplasticity may be a valuable predictor of the tDCS effect on pain scores decreases across the treatment.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/sangue , Fibromialgia/sangue , Fibromialgia/terapia , Avaliação de Processos e Resultados em Cuidados de Saúde , Córtex Pré-Frontal , Estimulação Transcraniana por Corrente Contínua , Adolescente , Adulto , Idoso , Método Duplo-Cego , Estudos de Viabilidade , Feminino , Humanos , Pessoa de Meia-Idade , Placebos , Estudo de Prova de Conceito , Adulto Jovem
8.
Artigo em Inglês | MEDLINE | ID: mdl-31403114

RESUMO

Introduction: According to the International Urogynecological Association and International Continence Society people with normal pelvic floor muscle function should have the ability to voluntarily and involuntarily contract and relax these muscles. However, many women are unaware of their pelvic floor, and it is estimated that about 30-50% do not know how to actively contract these muscles. Within this context, therapeutic strategies to improve pelvic floor muscle strength and function are particularly relevant. Aims: To compare the use of an intravaginal vibratory stimulus (IVVS) versus intravaginal electrical stimulation (IVES) on pelvic floor muscle functionality in women with pelvic floor dysfunctions who cannot voluntarily contract these muscles. Materials and methods: Randomized clinical trial performed at a tertiary care hospital from June 2016 to September 2017. The sample comprised adult women with pelvic floor dysfunction who were unable to contract their pelvic floor muscles voluntarily. Women with latex allergy or other allergies in the pelvic region, vaginal or urinary tract infection, gynecological cancer, significant pain on palpation, or pelvic floor training over the preceding 6 months were excluded. After baseline assessment, women that met the inclusion criteria were randomized to receive once-weekly 20-minute sessions of IVVS or IVES for 6 weeks. Results: Twenty-one women were randomly assigned to each group; 18 completed the IVVS and 17 completed the IVES protocols. The IVVS group presented a significant increase in PFM strength in relation to the IVES group (p = 0.026). There was a significant interaction between time and type of intervention for the same variable (p = 0.008) in the IVVS group. Conclusion: Both techniques were beneficial, but IVVS was significantly superior to IVES in improving pevic floor muscle strength. Additional studies are warranted to consolidate the utility of IVVS as a treatment modality for pelvic floor dysfunction.

9.
Appl Psychophysiol Biofeedback ; 42(2): 133-137, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28255635

RESUMO

Although biofeedback has been used as a first-line therapy for fecal incontinence, it is known to be time consuming and demands attendance to a hospital during the whole period of treatment. In this study, we describe a new biofeedback device specifically developed for home treatment of fecal incontinence, which consists of a microprocessor controlled unit able to register and store the anal pressure waves corresponding to exercises performed by patients at home. In order to test the new device, a pilot study including ten patients with fecal incontinence was conducted. Evaluation of patients before and after the biofeedback training showed significant improvement in manometric and clinical parameters of anal continence. The new method may improve compliance of patients with the training program and reduce their need to be supervised during the treatment. It might represent a new alternative for the treatment of fecal incontinence.


Assuntos
Biorretroalimentação Psicológica/métodos , Incontinência Fecal/terapia , Idoso , Canal Anal/fisiopatologia , Incontinência Fecal/fisiopatologia , Feminino , Humanos , Pessoa de Meia-Idade , Diafragma da Pelve/fisiopatologia , Projetos Piloto , Resultado do Tratamento
10.
Protein Pept Lett ; 23(9): 790-4, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27320837

RESUMO

Investigating interactions of designed peptide-based biomaterials with lipid membranes is important for applications in nanobiotechnology. Here the interaction of an ornithine-rich pH-responsive peptide called P11-5 with a model membrane was investigated employing Fourier transform infrared spectroscopy (FTIR). The results showed that in the range of pH 6.0-8.0 the peptide P11-5 shows spectral features which are evidence of the presence of peptides with antiparallel beta-sheet conformation (bands in the range 1625-1615 cm-1), as also spectral features which indicate the existence of random coil conformation (bands in the range 1640-1648 cm-1). Two types of membranes were used, 1,2- dipalmitoyl-sn-3-glycero-phosphocholine (DPPC) membranes with zwitterionic head groups and 1,2-dipalmitoyl-sn-glycero-3-[phospho-rac-(1-glycerol)] (sodium salt) (DPPG) membranes with anionic head groups. It was showed that there was a distinct peptide interaction under different pH values, pH 6.0, 7.0 and 8.0 for each type of lipid membrane with DPPC membrane preventing the peptide self-association even at basic pH, while for DPPG membrane there was a more evident peptide-lipid interaction. FTIR measurements indicate that in the presence of DPPC membrane the peptide was prevented to form beta-sheet aggregates at basic pH, while in the presence of DPPG membranes the self-association behavior of the peptide was more similar to its behavior when in aqueous solution in the absence of lipid membranes. Such results are important for the potential development of novel biomolecular nanostructured materials by the physico-chemical understanding of the peptide-lipid interactions.


Assuntos
Membrana Celular/metabolismo , Bicamadas Lipídicas/química , Ornitina/química , Peptídeos/metabolismo , Concentração de Íons de Hidrogênio , Modelos Biológicos , Modelos Moleculares , Conformação Molecular , Nanotecnologia , Peptídeos/química , Ligação Proteica , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Protein Pept Lett ; 22(6): 482-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25962066

RESUMO

Two shorter peptides derived from enterocin CRL35, a 43-mer bacteriocin, were synthesized i.e. the N-terminal fragment spanning from residues 1 to 15, and a 28-mer fragment that represents the C-terminal of enterocin CRL35, the residues 16 to 43. The separate peptides showed no activity when combined. On one hand, the 28-mer peptide displayed an unpredicted antimicrobial activity. On the other, 15- mer peptide had no consistent anti-Listeria effect. The dissociation constants calculated from experimental data indicated that all peptides could bind at similar extent to the sensitive cells. However, transmembrane electrical potential was not dissipated to the same level by the different peptides; whereas the full-length and the C-terminal 28-mer fragment induced almost full dissipation, 15-mer fragment produced only a slow and incomplete effect. Furthermore, a different interaction of each peptide with membranes was demonstrated based on studies carried out with liposomes, which led us to conclude that activity was related to structure rather than to net positive charges. These results open up the possibility of designing new peptides based on the 28-mer fragment with enhanced activity, which would represent a promising approach for combating Listeria and other pathogens.


Assuntos
Bacteriocinas/química , Bacteriocinas/farmacologia , Listeria/efeitos dos fármacos , Sequência de Aminoácidos , Bacteriocinas/síntese química , Bacteriocinas/genética , Lactobacillaceae/genética , Lipossomos/química , Potenciais da Membrana/efeitos dos fármacos , Viabilidade Microbiana/efeitos dos fármacos , Dados de Sequência Molecular
12.
Amino Acids ; 47(7): 1433-43, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25868656

RESUMO

Conjugate compounds constitute a new class of molecules of important biological interest mainly for the treatment of diseases such as cancer. The N-terminus region of cationic peptides has been described as important for their biological activity. The aim of this study was to evaluate the lytic peptide Hecate (FALALKALKKALKKLKKALKKAL) and the effect of conjugating this macromolecule with gallic acid (C7H6O5) in terms of structure, anti-cancer activity, and toxicity. An N-terminus GA-Hecate peptide conjugate was synthesized to provide information regarding the relationship between the amino-terminal region and its charge and the secondary structure and biological activity of the peptide; and the effects of gallic acid on these parameters. Peptide secondary structure was confirmed using circular dichroism (CD). The CD measurements showed that the peptide has a high incidence of α-helical structures in the presence of SDS and LPC, while GA-Hecate presented lower incidence of α-helical structures in the same chemical environment. An evaluation of the anti-cancer activity in HeLa cancer cells indicated that both peptides are active, but that coupling gallic acid at the N-terminus decreased the activity of the free peptide. GA-Hecate showed lower activity in non-tumor keratinocyte cells but higher hemolytic activity. Our findings suggest that the N-terminus of Hecate plays an important role in its activity against cervical cancer by affecting it secondary structure, toxicity, and hemolytic activity. This study highlights the importance of the N-terminus in antitumor activity and could provide an important tool for developing new anti-cancer drugs.


Assuntos
Antineoplásicos/farmacologia , Ácido Gálico/farmacologia , Hemolíticos/farmacologia , Meliteno/análogos & derivados , Sequência de Aminoácidos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Eritrócitos/efeitos dos fármacos , Feminino , Células HeLa , Humanos , Meliteno/farmacologia , Dados de Sequência Molecular , Neoplasias do Colo do Útero
13.
Open Respir Med J ; 8: 41-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25614771

RESUMO

PURPOSE: Study the repeatability of the evaluation of the perception of dyspnea using an inspiratory resistive loading system in healthy subjects. METHODS: We designed a cross sectional study conducted in individuals aged 18 years and older. Perception of dyspnea was assessed using an inspiratory resistive load system. Dyspnea was assessed during ventilation at rest and at increasing resistive loads (0.6, 6.7, 15, 25, 46.7, 67, 78 and returning to 0.6 cm H2O/L/s). After breathing in at each level of resistive load for two minutes, the subject rated the dyspnea using the Borg scale. Subjects were tested twice (intervals from 2 to 7 days). RESULTS: Testing included 16 Caucasian individuals (8 male and 8 female, mean age: 36 years). The median scores for dyspnea rating in the first test were 0 at resting ventilation and 0, 2, 3, 4, 5, 7, 7 and 1 point, respectively, with increasing loads. The median scores in the second test were 0 at resting and 0, 0, 2, 2, 3, 4, 4 and 0.5 points, respectively. The intra-class correlation coefficient was 0.57, 0.80, 0.74, 0.80, 0.83, 0.86, 0.91, and 0.92 for each resistive load, respectively. In a generalized linear model analysis, there was a statistically significant difference between the levels of resistive loads (p<0.001) and between tests (p=0.003). Dyspnea scores were significantly lower in the second test. CONCLUSION: The agreement between the two tests of the perception of dyspnea was only moderate and dyspnea scores were lower in the second test. These findings suggest a learning effect or an effect that could be at least partly attributed to desensitization of dyspnea sensation in the brain.

14.
J Invest Surg ; 26(2): 80-4, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23273175

RESUMO

Anti-reflux barrier (ARB) resistance may be useful to test new treatments for gastroesophageal reflux (GER). The ARB has been estimated by increasing gastric yield pressure (GYP) and gastric yield volume (GYV) in animal models but has not been validated. This study aimed to develop an experimental model suitable for assessing the ARB resistance to increasing intragastric pressure and volume and its reproducibility in a seven-day interval. Ten two-month-old female Large-White swine were studied. Intragastric pressure and volume were recorded using a digital system connected to a Foley catheter inserted through gastrostomy into the stomach. GYP and GYV were defined as the gastric pressure and volume able to yield gastric contents into the esophagus detected by esophageal pH. A sudden pH drop below 3 sustained during 5 min was considered diagnostic for gastric yield. Animals were studied again after seven days. On days 0 and 7, there were no significant differences for GYP (mean ± SD = 7.66 ± 3.02 mmHg vs. 7.07 ± 3.54 mmHg, p = .686) and GYV (636.70 ± 216.74 ml vs. 608.30 ± 276.66 ml; p = .299), respectively. Concordance correlation coefficient (ρc) was significant for GYP (ρc = 0.634, 95% CI = 0.141-0.829, p = .006), but not for GYV (ρc = 0.291, 95% CI = -0.118 to 0.774, p = .196). This study demonstrated an experimental model, assessing the ARB resistance. GYP seems to be a more reliable parameter than GYV for assessment of ARB resistance.


Assuntos
Refluxo Gastroesofágico/fisiopatologia , Pressão , Estômago/fisiologia , Animais , Junção Esofagogástrica/fisiologia , Feminino , Refluxo Gastroesofágico/prevenção & controle , Concentração de Íons de Hidrogênio , Manometria , Modelos Animais , Reprodutibilidade dos Testes , Suínos
15.
Asian Cardiovasc Thorac Ann ; 18(6): 521-8, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21149399

RESUMO

We describe a case series of 35 patients with either benign (14) or malignant (21) tracheal stenosis who were treated using a novel silicone stent, the HCPA-1, designed to prevent migration. Between March 2001 and September 2008, 13 women and 22 men received 41 HCPA-1 stents. The median duration of stenting in benign cases was 457 days (range, 4-2,961 days). Successful stent removal with curative results was accomplished in 2 patients with tracheomalacia and 1 with post-intubation stenosis. In malignant cases, the median duration of stenting was 162 days (range, 1-1,279 days). Five patients had tumor progression with obstruction requiring repeated laser resection, dilatation, or additional stents. Two patients died due to airway obstruction despite bronchoscopic intervention. Twelve patients with malignant lesions died with the stent in place. At the end of the study, 3 patients with malignant disease remained alive; 2 were lost to follow-up. The HCPA-1 stent proved to be safe, with no severe complications during the study period, and effective in improving quality of life with relief of dyspnea.


Assuntos
Obstrução das Vias Respiratórias/terapia , Broncopatias/terapia , Broncoscopia/instrumentação , Silicones , Stents , Estenose Traqueal/terapia , Adulto , Idoso , Obstrução das Vias Respiratórias/diagnóstico por imagem , Obstrução das Vias Respiratórias/etiologia , Obstrução das Vias Respiratórias/mortalidade , Brasil , Broncopatias/diagnóstico por imagem , Broncopatias/mortalidade , Broncoscopia/efeitos adversos , Cateterismo , Distribuição de Qui-Quadrado , Remoção de Dispositivo , Dispneia/etiologia , Dispneia/terapia , Feminino , Humanos , Intubação Intratraqueal/efeitos adversos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Neoplasias/complicações , Cuidados Paliativos , Modelos de Riscos Proporcionais , Desenho de Prótese , Radiografia , Fatores de Tempo , Estenose Traqueal/diagnóstico por imagem , Estenose Traqueal/etiologia , Estenose Traqueal/mortalidade , Traqueomalácia/complicações , Traqueostomia/efeitos adversos , Resultado do Tratamento
16.
J Biomech ; 42(15): 2466-71, 2009 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-19656514

RESUMO

The pelvic-floor muscles (PFM) play an important role in urinary and fecal continence. Several investigators have studied the PFM using intra-vaginal pressure measurements, but their methods have not been validated. We describe the characteristics of a probe transducer developed to measure PFM strength according to its dynamic response and the effects of temperature variation. This probe transducer was used to evaluate changes in the contraction strength of pelvic muscles in a group of patients who participated in a PFM training program. Experiments allowed the identification of the probe's characteristics at different temperatures, definition of a calibration equation, and measurements of the dynamic response to pressure pulse. Evaluation of patients before and after the PFM training program showed significant differences in the peak pressure achieved during the contraction (p<0.001) and in pressure-rise time (p<0.01). The tests performed with the probe allowed the characterization of the proposed transducer, and the intra-vaginal pressure measurements in volunteers undergoing a PFM training program allowed a quantitative evaluation of the PFM strength.


Assuntos
Manometria/instrumentação , Força Muscular , Músculo Esquelético/fisiopatologia , Diafragma da Pelve/fisiopatologia , Transdutores , Incontinência Urinária por Estresse/diagnóstico , Vagina/fisiopatologia , Desenho de Equipamento , Análise de Falha de Equipamento , Feminino , Humanos , Pessoa de Meia-Idade , Contração Muscular , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Surg Endosc ; 23(11): 2430-7, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19252945

RESUMO

BACKGROUND AND AIMS: Endoscopic augmentation of the esophagogastric junction (EGJ) with polymethylmethacrylate (PMMA) has been reported in an experimental short-term study. We assessed whether endoscopic augmentation of the EGJ with PMMA is durable, safe, and efficacious after 6 months in mini-pigs. METHODS: Ten mini-pigs were studied under anesthesia. After a pilot study in two animals, eight mini-pigs underwent lower esophageal sphincter (LES) manometry and gastrostomy with measurement of gastric yield volume (GYV) and gastric yield pressure (GYP). Endoscopic implantation of PMMA was performed aiming for the submucosa of the EGJ. Six months later, LES manometry and GYV and GYP measurements were repeated and animals were sacrificed, followed by microscopic analyses of the EGJ. RESULTS: Out of 32 implants (four per animal), 29 (91%) were identified as submucosal nodules postmortem. PMMA deposits were found at microscopic analysis in all animals and located as follows [mean (range)]: submucosa 61.5% (37.5-91%), muscularis propria 21.5% (0-58%), mucosa 11% (0-25%), and subserosa 6% (0-17%). Neither esophageal perforation nor death was observed. A significant increase in GYV (1,404 versus 905 ml; p = 0.02) and a borderline increase in GYP (8.1 versus 6.5 mmHg; p = 0.057) were detected 6 months later. CONCLUSIONS: Endoscopic augmentation of the esophagogastric junction with PMMA was durable and had no complications after 6 months. However, the occurrence of implants in the subserosa requires technical refinement before use in clinical trials.


Assuntos
Endoscopia Gastrointestinal/métodos , Junção Esofagogástrica/cirurgia , Refluxo Gastroesofágico/cirurgia , Polimetil Metacrilato/farmacologia , Procedimentos Cirúrgicos Reconstrutivos/métodos , Animais , Modelos Animais de Doenças , Esofagoscopia/métodos , Seguimentos , Gastroscopia/métodos , Manometria , Projetos Piloto , Falha de Prótese , Implantação de Prótese , Suínos , Porco Miniatura , Resistência à Tração , Resultado do Tratamento
18.
Int J Gynaecol Obstet ; 105(3): 218-22, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19232601

RESUMO

OBJECTIVE: To describe a new device for home treatment of urinary incontinence (UI) by comparing 3 conservative techniques and monitoring compliance and performance. METHODS: Thirty-two patients with UI were allocated to 1 of 3 intervention groups: pelvic floor muscle exercises (PFME; n=11) alone; PFME combined with biofeedback (n=10); or PFME combined with electrical stimulation (n=11). The outcomes assessed were: changes in quality of life score (QLS), urodynamic and perineometric parameters, episodes of urine loss, subjective assessment of improvement, and actual compliance and performance with treatment. RESULTS: Increased pelvic muscle contraction strength (P<0.05), improvement in QLS (P<0.02), and fewer episodes of urine leakage were observed in all 3 groups (P<0.05). Compliance was similar among the groups (P=0.201). CONCLUSION: All 3 techniques were effective for home treatment of UI, with significant control of symptoms and improved quality of life. The device effectively monitored compliance and performance of exercises.


Assuntos
Terapia por Estimulação Elétrica/métodos , Terapia por Exercício/métodos , Diafragma da Pelve , Incontinência Urinária/reabilitação , Adulto , Idoso , Biorretroalimentação Psicológica/métodos , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Contração Muscular , Cooperação do Paciente , Qualidade de Vida , Método Simples-Cego , Resultado do Tratamento , Urodinâmica
19.
J Biomed Mater Res B Appl Biomater ; 83(1): 216-21, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17410568

RESUMO

This article describes the development of a Nitinol tracheal stent (HCPA NiTi-stent) and its application in a feline animal model. Straight-annealed, bright-polished Nitinol wire (55.8%Ni-44.2%Ti) was weaved around a 40-mm-long metal fixture with 8-mm diameter. The prototypes were submitted to different times of shape-setting heat treatment (530 degrees C), which resulted in stents of different colors and caused some variation in length and diameter. The prototypes were then submitted to compression testing, and the most resistant pieces, requiring the greatest force to achieve a 25% reduction in diameter and presenting the least variation in length and diameter (dark blue, 9 min of heat treatment), were submitted to fatigue testing. After that, only dark blue stents were manufactured and implanted in felines. No migration, tracheal stenosis, or any other type of damage were observed after 40 weeks. The integrity of the tracheal wall in contact with the stent was confirmed by macro and microscopic analyses. The development and in vivo testing of the HCPA NiTi-stent were successful.


Assuntos
Ligas/química , Stents , Traqueia , Animais , Gatos , Humanos , Desenho de Prótese , Estresse Mecânico , Traqueia/anatomia & histologia , Traqueia/cirurgia
20.
Pediatr Crit Care Med ; 5(2): 152-6, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14987345

RESUMO

OBJECTIVE: To determine the prevalence and factors associated with oropharyngeal aspiration in pediatric patients submitted to mechanical ventilation and endotracheal intubation. DESIGN: Prospective cross-sectional study. SETTING: Four pediatric intensive care units. PATIENTS: Fifty infants and children with endotracheal intubation submitted to mechanical ventilation. INTERVENTIONS: Aspiration was determined by administering Evans blue dye in the oral cavity and searching the dye agent in the specimens obtained from two tracheal aspirates performed at 5- and 30-min intervals. During this period, the frequency of swallowing movements was continuously monitored using surface electromyography (biofeedback). The association between aspiration and age, sedation level, mean airway pressure, swallowing dynamics, and intubation route was tested using the chi-square and relative risk (95% confidence interval). Results also were adjusted by multivariate analysis. MEASUREMENTS AND MAIN RESULTS: The overall prevalence of aspi-ration was 28% (n = 14). At the univariate analysis, aspiration was associated with sedation level (p =.03), frequency of swallowing movements (p =.0003), and orotracheal route (p =.03). The relative risk (95% confidence interval) for aspiration was 2.92 (1.32-6.42) in patients considered to be inadequately sedated (Hartwig 8-18); 14.08 (1.99-99.67) in patients presenting frequent swallowing (>30 movements in 30 mins); and 5.57 (0.8-38.85) in patients with orotracheal intubation. The multivariate analysis identified that the orotracheal route (p =.03) and frequent swallowing movements (p =.0007) were independently associated with aspiration. CONCLUSIONS: Aspiration around the tracheal tube is a frequent finding (28%) in children undergoing mechanical ventilation. The frequent swallowing movements and the orotracheal intubation route were significantly associated with aspiration. These results suggest that the nasotracheal intubation route could be recommended as the first choice for reducing this potential clinical complication.


Assuntos
Intubação Intratraqueal/efeitos adversos , Pneumonia Aspirativa/etiologia , Respiração Artificial/efeitos adversos , Criança , Pré-Escolar , Estudos Transversais , Deglutição , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pneumonia Aspirativa/epidemiologia , Prevalência , Fatores de Risco
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