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101.
Abstract

Copaiba oleoresin (CPO), obtained from Copaifera landgroffii, is described as active to a large number of diseases and more recently in the endometriosis treatment. In this work, poly(lactic-co-glycolic acid) (PLGA) nanoparticles containing CPO were obtained using the design of experiments (DOE) as a tool to optimize the production process. The nanoparticles optimized by means of DOE presented an activity in relation to the cellular viability of endometrial cells. The DOE showed that higher amounts of CPO combined with higher surfactant concentrations resulted in better encapsulation efficiency and size distribution along with good stability after freeze drying. The encapsulation efficiency was over 80% for all produced nanoparticles, which also presented sizes below 300?nm and spherical shape. A decrease in viability of endometrial stromal cells from ectopic endometrium of patients with endometriosis and from eutopic endometriotic lesions was demonstrated after 48?h of incubation with the CPO nanoparticles. The nanoparticles without CPO were not able to alter the cell viability of the same cells, indicating that this material was not cytotoxic to the tested cells and suggesting that the effect was specific to CPO. The results indicate that the use of CPO nanoparticles may represent a promising alternative for the treatment of endometriosis.  相似文献   
102.
103.
Reaching movements made with hemiparetic upper limbs are often followed by compensatory trunk and shoulder-girdle movements, especially in reach-to-grasp strategies. We investigated the effect of restraint therapy on movement aiming at targets placed within arm reach. Eleven subjects were selected to participate in this study and were submitted to training with the trunk fixed to a chair during the reaching movement. Quantitative and qualitative scales (Modified Ashworth Scale, Fugl-Meyer Assessment Scale-upper limb section, Berg Balance Scale and Barthel Index) were used to evaluate reaching in three periods--pre-treatment, post-treatment and follow-up 3 months after training was completed. We found that in the arm section of the Fugl-Meyer Assessment Scale, pain (x2=8.22, P=0.016), proprioception (x2=6.00, P=0.049), flexor synergy (x2=6.07, P=0.048), wrist (x2=6.50, P=0.039), coordination velocity (x2=7.05, P=0.029) and the total score for the upper limb (x2=7.95, P=0.019) had statistical significance, especially in the pre-treatment and follow-up phases. The same happened using the Barthel Index (x2=8.33, P=0.016). Trunk restraint allowed patients with hemiparetic stroke to make use of active arm joint ranges that are present but not normally recruited during unrestrained arm reaching tasks. Appropriate treatments, such as trunk restraint, may be effective in uncovering latent movement patterns to maximize arm recovery in hemiparetic patients.  相似文献   
104.

Purpose:

Hypodontia is the congenital absence of one or more (up to six) permanent and/or deciduous teeth, being one of the most common alterations of the human dentition. Genetic polymorphisms are variations of DNA sequences occurring in a population. This study investigated whether G-915C single nucleotide polymorphism (SNPs) in the PAX9 gene promoter is associated with hypodontia in humans.

Material and Methods:

The polymorphism in region G/C-915 of PAX9 gene (NCBI ref SNP ID: rs 2073247) of 240 patients was analyzed, being 110 controls and 130 individuals with third molar agenesis. After DNA extraction, the region of interest was amplified by PCR technique using two different primers. The significance of the differences in observed frequencies of polymorphisms in both groups was assessed by odds-ratio and chi-squared test with 95% confidence interval.

Results:

Genotype CC was more frequent in patients with agenesis (11.5%) compared to the control (1.8%), while GG was more prevalent in the control group (39.1%) compared to the individuals with agenesis (26.2%).

Conclusion:

These data showed that the allele C could be associated with the third molar agenesis.  相似文献   
105.
OBJECTIVE: To reevaluate the clinical impact of external positive end-expiratory pressure (external-PEEP) application in patients with severe airway obstruction during controlled mechanical ventilation. The controversial occurrence of a paradoxic lung deflation promoted by PEEP was scrutinized. DESIGN: External-PEEP was applied stepwise (2 cm H(2)O, 5-min steps) from zero-PEEP to 150% of intrinsic-PEEP in patients already submitted to ventilatory settings minimizing overinflation. Two commonly used frequencies during permissive hypercapnia (6 and 9/min), combined with two different tidal volumes (VT: 6 and 9 mL/kg), were tested. SETTING: A hospital intensive care unit. PATIENTS: Eight patients were enrolled after confirmation of an obstructive lung disease (inspiratory resistance, >20 cm H(2)O/L per sec) and the presence of intrinsic-PEEP (> or =5 cm H(2)O) despite the use of very low minute ventilation. INTERVENTIONS: All patients were continuously monitored for intra-arterial blood gas values, cardiac output, lung mechanics, and lung volume with plethysmography. MEASUREMENTS AND MAIN RESULTS: Three different responses to external-PEEP were observed, which were independent of ventilatory settings. In the biphasic response, isovolume-expiratory flows and lung volumes remained constant during progressive PEEP steps until a threshold, beyond which overinflation ensued. In the classic overinflation response, any increment of external-PEEP caused a decrease in isovolume-expiratory flows, with evident overinflation. In the paradoxic response, a drop in functional residual capacity during external-PEEP application (when compared to zero-external-PEEP) was commonly accompanied by decreased plateau pressures and total-PEEP, with increased isovolume-expiratory flows. The paradoxic response was observed in five of the eight patients (three with asthma and two with chronic obstructive pulmonary disease) during at least one ventilator pattern. CONCLUSIONS: External-PEEP application may relieve overinflation in selected patients with airway obstruction during controlled mechanical ventilation. No a priori information about disease, mechanics, or ventilatory settings was predictive of the response. An empirical PEEP trial investigating plateau pressure response in these patients appears to be a reasonable strategy with minimal side effects.  相似文献   
106.
Functional foods have nutritional properties and organic functions, which are beneficial to health. Certain types of functional food components are so‐called phytoestrogens, non‐steroidal compounds derived from the metabolism of precursors contained in plants, which originate secondary metabotypes known to induce biological responses and by mimicry or modulating the action of endogenous estrogen. These molecules are involved in several physiological and pathological processes related to reproduction, bone remodeling, skin, cardiovascular, nervous, immune systems, and metabolism. This review aimed to present an overview of phytoestrogens regarding their chemical structure, actions, and effects in the organism given several pathologies. Several studies have demonstrated beneficial phytoestrogen actions, such as lipid profile improvement, cognitive function, menopause, oxidative stress, among others. Phytoestrogens effects are not completely elucidated, being necessary future research to understand the exact action mechanisms, whether they are via estrogen receptor or whether other hidden mechanisms produce these effects. Thus, this review makes a general approach to the phytoestrogen actions, beneficial effects, risk and limitations. However, the complexities of biological effects after ingestion of phytoestrogens and the differences in their metabolism and bioavailability indicate that interpretation of either risk or benefits needs to be made with caution.  相似文献   
107.

Background

A new, simple and accurate stability-indicating reverse phase high performance liquid chromatography method was developed and validated during the early stage of drug development of an oral lyophilizate dosage form of cetirizine dihydrochloride.

Methods

For RP-HPLC analysis it was used an Eclipse XDB C8 column 150 mm × 4.6 mm, 5 μm (Agilent columns, Barcelona, Spain) as the stationary phase with a mobile phase consisted of a mixture of 0.2 M K2HPO4 pH 7.00 and acetonitrile (65:35, v/v) at a flow rate of 1 mL min −1. Detection was performed at 230 nm using diode array detector. The method was validated in accordance with ICH guidelines with respect to linearity, accuracy, precision, specificity, limit of detection and quantification.

Results

The method results in excellent separation between the drug substance and its stress-induced degradation products. The peak purity factor is >950 for the drug substance after all types of stress, which confirms the complete separation of the drug substance peak from its stress induced degradation products.Regression analysis showed r2 > 0.999 for cetirizine dihydrochloride in the concentration range of 650 μg mL −1 to 350 μg mL−1 for drug substance assay and a r2 > 0.999 in the concentration range of 0.25 μg mL−1 to 5 μg mL−1 for degradation products. The method presents a limit of detection of 0.056 μg mL −1 and a limit of quantification of 0.25 μg mL−1. The obtained results for precision and accuracy for drug substance and degradation products are within the specifications established for the validation of the method.

Conclusions

The proposed stability-indicating method developed in the early phase of drug development proved to be a simple, sensitive, accurate, precise, reproducible and therefore useful for the following stages of the cetirizine dihydrochloride oral lyophilizate dosage form development.  相似文献   
108.

Objective

To evaluate patients'' quality of life aspects after pacemaker implantation, relating it to gender, age, and implantation timespan.

Methods

A total of 107 clinically stable patients of both genders (49.5% women and 50.5% men) over 18 years old (average 69.3±12.6 years) and presenting an implantation timespan of three to 12 months (average 6.36±2.99 months) were evaluated. The evaluation included personal, clinical, and implant data as well as quality of life questionnaires (AQUAREL and SF-36). Statistical analysis was conducted using the t test and Pearson correlation, with a 5% significance level.

Results

The lowest SF-36 score referred to physical aspects, and the highest score referred to social aspects. In AQUAREL, the lowest score referred to dyspnea, and the highest referred to discomfort. There was a significant association between gender and quality of life in SF-36 (physical functioning and emotional aspects) and in AQUAREL (dyspnea). A negative correlation was observed between age and quality of life (functional capacity in SF-36, and discomfort in AQUAREL) in relation to implantation timespan, a correlation with vitality from SF-36.

Conclusion

Lower quality of life scores were found in physical aspects and dyspnea; and higher scores in social aspects and discomfort. Men presented higher quality of life scores related to physical functioning, emotional aspects and dyspnea. As age increases, quality of life worsens regarding functional capacity and discomfort; and the longer the pacemaker implantation timespan, the worse quality of life when it comes to vitality. Gender, age, and implantation timespan influence quality of life; thus, these variables must be considered in strategies for improving quality of life of patients with pacemakers.  相似文献   
109.
SCH 900567 is a specific inhibitor of tumor necrosis factor‐alpha converting enzyme and is a potential candidate for the treatment of rheumatoid arthritis. [3H]SCH 900567 was synthesized to support the initial drug metabolism and pharmacokinetics studies. Stable isotope‐labeled [13C3, 15N]SCH 900567 was requested by the bioanalytical group as an internal standard for Liquid chromatography‐tandem mass spectrometry (LC‐MS/MS) method development as well as by the drug metabolism and pharmacokinetics group for a potential microdose study. [13C3, 15N]SCH 900567 is synthesized via a linear sequence of seven steps from commercially available materials in 2.6% overall yield. [14C]SCH 900567 was needed for a quantitative whole body autoradiography studies and was prepared from unlabeled Active Pharmaceutical Ingredient (API) via hydrolysis of the hydantoin moiety followed by rebuilding the hydantoin ring using potassium [14C]cyanate to give the desired product in 42.8% overall yield. Activation of the hydantoin moiety of SCH 900567 to achieve hydrolysis followed by derivatization of the resulting amino acid to avoid decarboxylation during cyclization is also discussed.  相似文献   
110.
Dissemination of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in healthcare institutions affects both patients and health-care workers (HCW), as well as the institutional capacity to provide essential health services. Here, we investigated an outbreak of SARS-CoV-2 in a “non-COVID-19” hospital ward unveiled by massive testing, which challenged the reconstruction of transmission chains. The contacts network during the 15-day period before the screening was investigated, and positive SARS-CoV-2 RNA samples were subjected to virus genome sequencing. Of the 245 tested individuals, 48 (21 patients and 27 HCWs) tested positive for SARS-CoV-2. HCWs were mostly asymptomatic, but the mortality among patients reached 57.1% (12/21). Phylogenetic reconstruction revealed that all cases were part of the same transmission chain. By combining contact tracing and genomic data, including analysis of emerging minor variants, we unveiled a scenario of silent SARS-CoV-2 dissemination, mostly driven by the close contact within the HCWs group and between HCWs and patients. This investigation triggered enhanced prevention and control measures, leading to more timely detection and containment of novel outbreaks. This study shows the benefit of combining genomic and epidemiological data for disclosing complex nosocomial outbreaks, and provides valuable data to prevent transmission of COVID-19 in healthcare facilities.  相似文献   
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