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151.
Environmental Biology of Fishes - The objective was to explore levels of persistence and stability of a Neotropical fish assemblage in a typical Serra do Mar stream (Southeast Brazil) over...  相似文献   
152.
Glutathione-S-transferase(s) (GST) enzyme from Brugia malayi has been exploited as a target in lymphatic filariasis therapeutics. An active GST is a homodimer of a 208 residue long monomer consisting of two domains, a smaller α/β domain and a larger α domain. The components of the glutathione (GSH) system, mainly GST enzymes, are critical antioxidant and detoxification system responsible for the long-term existence of filarial worms in mammalian host; hence they are major chemotherapeutic targets in filarial species. In the present study, 58 phytochemicals from 10 plants, predicted and reported to have potential nematicidal activity and ADMET satisfaction, have been docked to GST enzyme of B. malayi to assess their binding affinity and consequently their inhibitory activity. A comparative study has been made with commonly employed chemotherapeutic GST inhibitors such as cibacron-blue, butylated hydroxyanisole, hexyl glutathione and ethacrynic acid. In vitro effects of potential drug like compound from in silico results have been done for validation of docking studies. In vitro assay revealed efficacy in GST inhibition in the following compounds: linalool (97.50%), alpha-pinene (90.00%), strychnine (87.49%), vanillin (84.99%), piperine (79.99%), isoeugenol (62.49%), curcumin (57.49%), beta-caryophyllene (39.50%), cinnamic acid (27.49%), capsaicin (19.99%), citronellol (19.99%) and geraniol (17.49%). An online database () has been developed, which will serve as a useful repository of information on GST inhibitors for future development of drugs against filarial nematodes. These findings thus suggest that the above phytochemicals could be potentially developed as lead molecules for targeting GST of lymphatic filarial parasites.  相似文献   
153.

Objective

The aim of this study was to investigate the effects of chronic treatment with atrial natriuretic peptide (ANP) on renal function, nitric oxide (NO) system, oxidative stress, collagen content and apoptosis in kidneys of spontaneously hypertensive rats (SHR), as well as sex-related differences in the response to the treatment.

Methods

10 week-old male and female SHR were infused with ANP (100 ng/h/rat) or saline (NaCl 0.9%) for 14 days (subcutaneous osmotic pumps). Systolic blood pressure (SBP) was recorded and diuresis and natriuresis were determined. After treatment, renal NO synthase (NOS) activity and eNOS expression were evaluated. Thiobarbituric acid-reactive substances (TBARS), glutathione concentration and glutathione peroxidase (GPx) and superoxide dismutase (SOD) activities were determined in the kidney. Collagen was identified in renal slices by Sirius red staining and apoptosis by Tunel assay.

Results

Female SHR showed lower SBP, oxidative stress, collagen content and apoptosis in kidney, and higher renal NOS activity and eNOS protein content, than males. ANP lowered SBP, increased diuresis, natriuresis, renal NOS activity and eNOS expression in both sexes. Renal response to ANP was more marked in females than in males. In kidney, ANP reduced TBARS, renal collagen content and apoptosis, and increased glutathione concentration and activity of GPx and SOD enzymes in both sexes.

Conclusions

Female SHR exhibited less organ damage than males. Chronic ANP treatment would ameliorate hypertension and end-organ damage in the kidney by reducing oxidative stress, increasing NO-system activity, and diminishing collagen content and apoptosis, in both sexes.  相似文献   
154.

Background

Preterm birth is a serious public health problem, as it is linked to high rates of neonatal and child morbidity and mortality, with Brazil listed among the countries with the ten highest numbers of premature births. Nonetheless, knowledge is scarce regarding prematurity and associated factors in mid-sized cities. The objective of this study was to analyze the trend of preterm births and associated factors in a municipality located in the state of Paraná, Brazil.

Methods

This was an ecological time series study of births recorded into the Live Birth Information System for residents of Maringá, Paraná, Brazil, between 2000 and 2013. The polynomial regression model was used for trend analysis of preterm birth, characteristics of the mother, gestation and delivery, and newborn. The association with preterm birth was analyzed using odds ratio (OR).

Results

A total of 61,634 live births were analyzed, of which 5,632 were preterm births. Prematurity increased from 7.9% in 2000 to 11.2% in 2013 –an average increase of 0.54% per year (r2 = 0.93)–with a growing share of moderate preterm births (32 to <37 weeks), which rose from 7.0% in 2000 to 9.7% in 2013. Between 2011 and 2013, multiple pregnancy (OR = 16.64; CI = 13.24–20.92), inadequate number of prenatal visits (OR = 2.81; CI = 2.51–3.15), Apgar score below 7 at 1 (OR = 4.07; CI = 3.55–4.67) and 5 minutes (OR = 10.88; CI = 7.71–15.36), low birth weight (OR = 38.75; CI = 33.72–44.55) and congenital malformations (OR = 3.18; CI = 2.14–4.74) were associated with preterm birth. A growing trend was observed for multiple pregnancies, with an average annual increase of 0.32% (r2 = 0.90), as well as for C-section birth (2.38% yearly increase). Of all newborn characteristics, Apgar score below 7 at 5 minutes (-0.19% per year) and low birth weight (-1.43%) decreased, whereas congenital malformations rose (0.20% per year).

Conclusions

Efforts are required to prevent premature delivery, particularly during the moderate period, as well as greater care during the prenatal period towards expectant mothers bearing multiple pregnancies, birth defects, in addition to reducing C-section birth as it may be linked to preterm birth.  相似文献   
155.
The importance of plant-microbe associations for the invasion of plant species have not been often tested under field conditions. The research sought to determine patterns of change in microbial communities associated with the establishment of invasive plants with different taxonomic and phenetic traits. Three independent locations in Virginia, USA were selected. One site was invaded by a grass (Microstegium vimineum), another by a shrub (Rhamnus davurica), and the third by a tree (Ailanthus altissima). The native vegetation from these sites was used as reference. 16S rRNA and ITS regions were sequenced to study root-zone bacterial and fungal communities, respectively, in invaded and non-invaded samples and analyzed using Quantitative Insights Into Microbial Ecology (QIIME). Though root-zone microbial community structure initially differed across locations, plant invasion shifted communities in similar ways. Indicator species analysis revealed that Operational Taxonomic Units (OTUs) closely related to Proteobacteria, Acidobacteria, Actinobacteria, and Ascomycota increased in abundance due to plant invasions. The Hyphomonadaceae family in the Rhodobacterales order and ammonia-oxidizing Nitrospirae phylum showed greater relative abundance in the invaded root-zone soils. Hyphomicrobiaceae, another bacterial family within the phyla Proteobacteria increased as a result of plant invasion, but the effect associated most strongly with root-zones of M. vimineum and R. davurica. Functional analysis using Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) showed bacteria responsible for nitrogen cycling in soil increased in relative abundance in association with plant invasion. In agreement with phylogenetic and functional analyses, greater turnover of ammonium and nitrate was associated with plant invasion. Overall, bacterial and fungal communities changed congruently across plant invaders, and support the hypothesis that nitrogen cycling bacteria and functions are important factors in plant invasions. Whether the changes in microbial communities are driven by direct plant microbial interactions or a result of plant-driven changes in soil properties remains to be determined.  相似文献   
156.

Background

Bruxism is a parafunctional habit characterized by grinding and/or clenching of the teeth. It may happen while awake (awake bruxism) or while sleeping (sleep bruxism). In adults, the prevalence is 20% for the awake bruxism and 8% for the sleep bruxism. Peripheral, central, and psychosocial factors influence the disorder, which may predispose to pain in the masticatory muscles and neck, headache, decreased pain thresholds in the masticatory and cervical muscles, limitation mandibular range of motion, sleep disorders, stress, anxiety, depression, and overall impairment of oral health. The aim of this study is to compare two distinct physical therapy interventions with dental treatment in pain, mandibular range of motion, sleep quality, anxiety, stress, depression, and oral health in individuals with bruxism.

Methods/Design

Participants will be randomized into one of three groups: Group 1 (n?=?24) intervention will consist of massage and stretching exercises; Group 2 (n?=?24) will consist of relaxation and imagination therapies; and Group 3 (n?=?24) will receive dental treatment. The evaluations will be performed at baseline, immediately after treatment, and at 2-month follow-up. Pain intensity will be assessed using the visual analogical scale, while pain thresholds will be determined using dolorimetry. Mandibular range of motion will be assessed using digital pachymeter. Sleep quality will be assessed by the Pittsburgh Sleep Quality Index, anxiety by the State-Trait Anxiety Inventory, stress by the Perceived Stress Scale-10, depression by the Beck Depression Inventory, and oral health will be assessed using the Oral Health Impact Profile - 14. Significance level will be determined at the 5% level.

Discussion

This project describes the randomization method that will be used to compare two physical therapy interventions with dental treatment in the management of pain, mandibular range of motion, sleep quality, anxiety, stress, depression, and oral health in individuals with bruxism. The study will support the practice of evidence-based physical therapy for individuals with bruxism. Data will be published after study is completed.

Trial registration

ClinicalTrials.gov, NCT01778881  相似文献   
157.
158.
Myoclonic epilepsy with ragged red fibers (MERRF) is a mitochondrial disease that is characterized by myoclonic epilepsy with ragged red fibers (RRF) in muscle biopsies. The aim of this study was to analyze Brazilian patients with MERRF. Six patients with MERRF were studied and correlations between clinical findings, laboratory data, electrophysiology, histology and molecular features were examined. We found that blood lactate was increased in four patients. Electroencephalogram studies revealed generalized epileptiform discharges in five patients and generalized photoparoxysmal responses during intermittent photic stimulation in two patients. Muscle biopsies showed RRF in all patients using modified Gomori-trichrome and succinate dehydrogenase stains. Cytochrome c oxidase (COX) stain analysis indicated deficient activity in five patients and subsarcolemmal accumulation in one patient. Molecular analysis of the tRNA(Lys) gene with PCR/RFLP and direct sequencing showed the A8344G mutation of mtDNA in five patients. The presence of RRFs and COX deficiencies in muscle biopsies often confirmed the MERRF diagnosis. We conclude that molecular analysis of the tRNA(Lys) gene is an important criterion to help confirm the MERRF diagnosis. Furthermore, based on the findings of this study, we suggest a revision of the main characteristics of this disease.  相似文献   
159.
160.
Heteroxenic and monoxenic trypanosomatids were screened for the presence of actin using a mouse polyclonal antibody produced against the entire sequence of the Trypanosoma cruzi actin gene, encoding a 41.9 kDa protein. Western blot analysis showed that this antibody reacted with a polypeptide of approximately 42 kDa in the whole-cell lysates of parasites targeting mammals (T. cruzi, Trypanosoma brucei and Leishmania major), insects (Angomonas deanei, Crithidia fasciculata, Herpetomonas samuelpessoai and Strigomonas culicis) and plants (Phytomonas serpens). A single polypeptide of approximately 42 kDa was detected in the whole-cell lysates of T. cruzi cultured epimastigotes, metacyclic trypomastigotes and amastigotes at similar protein expression levels. Confocal microscopy showed that actin was expressed throughout the cytoplasm of all the tested trypanosomatids. These data demonstrate that actin expression is widespread in trypanosomatids.  相似文献   
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