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991.
Non-viral gene delivery using exogenous microRNAs is a potential strategy for fighting cancers with poor prognosis and which lack specific therapies, such as triple-negative breast cancer (TNBC). Herein we report the synthesis of six nontoxic electrostatic polymeric nanocapsules (P1 to P6) for microRNA delivery in TNBC cells. 1H Nuclear Magnetic Resonance (NMR) spectroscopy and Scanning Electron Microscopy (SEM) were used to characterize the nanopolyplexes, synthesized with Poly(L-Lysine) and hyaluronic acid (Ha). Studies on the activity of the ternary HA/PLI/miRNA-34 nanopolyplexes towards TNBC cell line MDA-MB-231 were conducted. The nanopolyplexes mediated intracellular restoration of tumor suppressor miR34a was evaluated by using Western blotting to quantify the expression level of the Bcl-2 protein. The results suggest that the P5, with a ratio PLI/Ha of 0.05, was the most promising for the delivery of miR-34a into TNBC cells; the P5 nanocapsules were able to reduce Bcl-2 expression at a protein level, and had an effect in the overall cell viability after 24 h treatment.  相似文献   
992.

Introduction

Muscle dysfunction is one of the most extensively studied manifestations of COPD. Metabolic changes in muscle are difficult to study in vivo, due to the lack of non-invasive techniques. Our aim was to evaluate metabolic activity simultaneously in various muscle groups in COPD patients.

Methods

Thirty-nine COPD patients and 21 controls with normal lung function, due to undergo computed axial and positron emission tomography for staging of localized lung lesions were included. After administration of 18-fluordeoxyglucose, images of 2 respiratory muscles (costal and crural diaphragm, and rectus abdominus) and 2 peripheral muscles (brachial biceps and quadriceps) were obtained, using the standard uptake value as the glucose metabolism index.

Results

Standard uptake value was higher in both portions of the diaphragm than in the other muscles of all subjects. Moreover, the crural diaphragm and rectus abdominus showed greater activity in COPD patients than in the controls (1.8 ± 0.7 vs 1.4 ± 0.8; and 0.78 ± 0.2 vs 0.58 ± 0.1; respectively, P < .05). A similar trend was observed with the quadriceps. In COPD patients, uptake in the two respiratory muscles and the quadriceps correlated directly with air trapping (r = 0.388, 0.427 and 0.361, respectively, P < .05).

Conclusions

There is greater glucose uptake and metabolism in the human diaphragm compared to other muscles when the subject is at rest. Increased glucose metabolism in the respiratory muscles (with a similar trend in their quadriceps) of COPD patients is confirmed quantitatively, and is directly related to the mechanical loads confronted.  相似文献   
993.
Fragility fractures resulting from low‐trauma events such as a fall from standing height are associated with osteoporosis and are very common in older people, especially women. Three single nucleotide polymorphisms (SNPs) at the COL1A1 gene (rs1107946, rs11327935, and rs1800012) have been widely studied and previously associated with bone mineral density (BMD) and fracture. A rare haplotype (T‐delT‐T) of these three SNPs was found to be greatly overrepresented in fractured individuals compared with nonfractured controls, thus becoming a good candidate for predicting increased fracture risk. The aim of our study was to assess the association of this haplotype with fracture risk in Spanish individuals. We recruited two independent groups of ~100 patients with hip fracture (a total of 203 individuals) and compared the genotype and haplotype distributions of the three SNPs in the fractured patients with those of 397 control individuals from the BARCOS Spanish cohort. We found no association with risk of fracture at the genotype level for any of the SNPs, and no differences in the SNP frequencies between the two groups. At the haplotype level, we found no association between the T‐delT‐T haplotype and fracture. However, we observed a small but significant (p = 0.03) association with another rare haplotype, G‐insT‐T, which was slightly overrepresented in the patient group. © 2012 American Society for Bone and Mineral Research.  相似文献   
994.

Rationale

Carbon monoxide synthetized by inducible heme oxygenase (HO-1) exerts potent anti-inflammatory and antinociceptive effects during acute and neuropathic pain, but its role in the modulation of chronic inflammatory pain and the possible involvement of nitric oxide in this action remain unknown.

Objectives and methods

The antiallodynic and antihyperalgesic effects of a carbon monoxide releasing molecule, tricarbonyldichlororuthenium(II) dimer (CORM-2), daily administered from days 4 to 14 after complete Freund's adjuvant (CFA) injection in wild-type (WT), neuronal (NOS1-KO), and inducible (NOS2-KO) nitric oxide synthases knockout mice, were evaluated using von Frey filaments and plantar tests. Effects of CORM-2 treatment on the expression of HO-1, NOS1, and NOS2 at 14 days after inflammation induction were assessed by Western blot.

Results

Main inflammatory pain symptoms induced by CFA in WT, NOS1-KO, and NOS2-KO mice were significantly reduced in a time-dependent manner by CORM-2 treatment. In all genotypes, inflammation increased the dorsal root ganglia and paw expression of HO-1, but CORM-2 treatment only over-expressed this enzyme in the paw of all genotypes. The increased NOS1 expression induced by inflammation in WT mice was abolished by CORM-2 treatment, while there was no effect of the inflammation in neither CORM-2 treatment in the expression of NOS2 in WT and NOS1-KO mice.

Conclusions

CORM-2 treatment inhibits inflammatory pain through enhancing HO-1 paw expression in all genotypes and reducing NOS1 over-expression in WT mice. An interaction between HO-1/carbon monoxide and NOS1/nitric oxide systems was also demonstrated. CORM-2 treatment may represent a new approach for management chronic inflammatory pain.  相似文献   
995.
996.
OBJECTIVE: To assess delivery outcomes in women with placental malaria who presented at public hospitals in Kisumu, a holoendemic region in western Kenya. METHODS: A cross-sectional study using both histology and molecular biology was conducted with 90 consecutive pregnant women who presented at 3 hospitals during a 2-week period. Data collectors completed standardized questionnaires using each patient's hospital record and physical examination results, and registered birth indices such as weight, head circumference, and weight-head ratio. Malaria infection of the placenta was assessed using a molecular biology approach (for genomic differences among parasite species) as well as histology techniques. Of the 5 histologic classes of placental infection, class 1 corresponds to active infection and class 4 to past infection; class 2 and 3 to active chronic infection; and class 5 to uninfected individuals. Plasmodium species typing was determined by polymerase chain reaction amplification of the parasite's genome. RESULTS: In newborns at term, low birth weight was directly associated with classes 2 and 4 of placental infection (P = 0.053 and P = 0.003, respectively), and differences in birth weight remained significant between the 5 classes (P < 0.001) even after adjusting for parity and mother's age. Plasmodium falciparum was the only detected parasite. CONCLUSIONS: In Kisumu, infection with P. falciparum is an important cause of low birth weight and morbidity when it is associated with histologic classes 2 and 4 of placental infection. Moreover, polymerase chain reaction assays should be supported by ministries of health as an ancillary method of collecting data for malaria control during pregnancy and providing a baseline for future interventions.  相似文献   
997.
998.
Pheochromocytoma is rarely observed during pregnancy and not easily diagnosed, especially since the clinical manifestations may mimic common gravid hypertension. The maternal and foetal prognosis depends on early diagnosis and multidisciplinary management preparing for tumor resection. Appropriate laboratory tests easily provide the positive diagnosis, if they are ordered. The tumor is localized by ultrasonography or scanner. By prescribing an alpha-blocker, it is possible to prepare there section as a function of term, before or after delivery. This strategy makes it possible to reduce a maternal death and foetal which is very high when the diagnosis is ignored.  相似文献   
999.
IntroductionThe wave of immigration in Spain in the last 10 years has had major consequences in the provision of key public services. In the present study, we examined the effect of this population shock on the demand for private health insurance.MethodsUsing data from the National Health Survey for 2001, 2003 and 2006, we estimated discrete choice models to analyze the demand for dual coverage (public and private insurance) and the demand for private coverage among civil servants.ResultsThe results suggest that both the percentage of immigrants and the increase in the population resulted in greater demand for private health insurance (social security sample), mainly in groups with a middle-to-high income and with children or with a greater choice of private healthcare provider (in the sample of civil servants). In both cases, private healthcare was sought to gain access to specialized and emergency services more rapidly. The marginal effect obtained by using the variable of the percentage of immigrants was much higher in the sample of civil servants (about 0.20) than in the social security sample (0.05).ConclusionsAlthough immigrants tend to enjoy better health and use health services (with the exception of emergencies) less frequently than Spaniards, this collective has led to a significant increase in the demand for healthcare and, especially, private health insurance.  相似文献   
1000.
A 48-year-old woman with a diagnosis of breast carcinoma was treated with adjuvant chemotherapy through a central venous catheter with subcutaneous reservoir (Port-A-Cath). While doxorubicin was administered, the patient presented thoracic pain and breathing distress due to superior vena cava perforation by the central catheter and subsequent extravasation of the drug into the mediastinum. The patient recovered without sequelae with conservative therapy. Cytostatic extravasation via central catheter is an uncommon complication in clinical practice. In this paper we present the first doxorubicin extravasation through a central catheter in adults and review the only ten cases found in the literature.  相似文献   
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