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71.
Parasitology Research - The treatment of cutaneous leishmaniasis in associated with several adverse effects and therapeutic failure, resulting in patients’ abandonment of treatment. Research...  相似文献   
72.
The thermal stability of several isotactic polypropylenes and propylene‐co‐1‐nonene copolymers is assessed under nitrogen by means of thermogravimetric analysis (TGA). The samples involve wide ranges of molecular weight, isotactic average length, and 1‐nonene content, in order to perform a comprehensive analysis of the effect that chain features exert on the apparent activation energy (Ea), in the initial stages of the molten state degradation. The degradation process correlates with chain mobility and, accordingly, with chain features that are linked to. Thus, microstructure and chain size are found to play a key role. In fact, isotactic average length of propylene sequences and molecular weight are driving factors in the Ea required for main chain thermal scission.  相似文献   
73.
74.
Minimal residual disease (MRD) assessment is an essential tool in contemporary acute lymphoblastic leukemia (ALL) protocols, being used for therapeutic decisions such as hematopoietic stem cell transplantation in high‐risk patients. However, a significant proportion of adult ALL patients with negative MRD still relapse suggesting that other factors (ie, molecular alterations) must be considered in order to identify those patients with high risk of disease progression. We have identified partial IKZF1 gene deletions and CDKN2A/B deletions as markers of disease recurrence and poor survival in a series of uniformly treated adolescent and adult Philadelphia chromosome‐negative B‐cell progenitor ALL patients treated according to the Programa Español de Tratamientos en Hematología protocols. Importantly, CDKN2A/B deletions showed independent significance of MRD at the end of induction, which points out the need for treatment intensification in these patients despite being MRD‐negative after induction therapy.  相似文献   
75.
Introduction: Allergic diseases constitute one of the most common causes of chronic illness in developed countries. The main mechanism determining allergy is an imbalance between Th1 and Th2 response towards Th2.

Areas covered: This review describes the mechanisms underlying the natural tolerance to food components and the development of an allergic response in sensitized individuals. Furthermore, therapeutic approaches proposed to manage these abnormal immunologic responses food are also presented and discussed.

Expert opinion: In the past, management of food allergies has consisted of the education of patients to avoid the ingestion of the culprit food and to initiate the therapy (e.g. self-injectable epinephrine) in case of accidental ingestion. In recent years, sublingual/oral immunotherapies based on the continuous administration of small amounts of the allergen have been developed. However, the long periods of time needed to obtain significant desensitization and the generation of adverse effects, limit their use. In order to solve these drawbacks, strategies to induce tolerance are being studied, such as the use of either adjuvant immunotherapy in order to facilitate the reversion of the Th2 response towards Th1 or the use of monoclonal antibodies to block the main immunogenic elements.  相似文献   

76.
Introduction: Obsessive-compulsive disorder (OCD) is a severe neuropsychiatric illness estimated to affect between 1–3% of the population. In today’s literature, there are a number well-validated and convincing animal models of OCD described.

Areas covered: Herein, the authors look at the role that animal models of OCD (including transgenic models, deer mouse stereotypy, quinpirole sensitization, post-training signal attenuation, and mouse marble burying) have played in determining the current directions of OCD drug discovery. Specifically, the article reviews new OCD drug therapies currently under investigation including drugs that target glutamate, dopamine, serotonin, and endocannabinoid systems. The authors review the published results of these clinical trials, and critically examine the contribution of animal models to the development of these novel therapies.

Expert opinion: Nitric oxide inhibitors, oxycarbazepine, and modulators of serotonin and metabotropic glutamate receptors should be further explored in animal models as well as in clinical trials. Pregabalin, topiramate, lamotrigine, sarcosine, minocycline, L-carnosine, celecoxib, and ondansetron, which have shown promise in clinical trials, should be explored in animal models with the goal of understanding the neurobiology of their effects. A multidisciplinary, interactive approach to OCD drug discovery, where animal models generate neurobiological hypotheses that can be tested in the clinic, and vice versa, should be cultivated.  相似文献   

77.
Objective: Parkinson's disease (PD) is characterized by deterioration of the nigrostriatal system and associated with chronic neuroinflammation. Glial activation has been associated with regulating the survival of dopaminergic neurons and is thought to contribute to PD through the release of proinflammatory and neurotoxic factors, such as reactive nitric oxide (NO) that triggers or exacerbates neurodegeneration in PD. Polyunsaturated fatty acids (PUFAs) exert protective effects, including antiinflammatory, antiapoptotic, and antioxidant activity, and may be promising for delaying or preventing PD by attenuating neuroinflammation and preserving dopaminergic neurons. The present study investigated the effects of fish oil supplementation that was rich in PUFAs on dopaminergic neuron loss, the density of inducible nitric oxide synthase (iNOS)-immunoreactive cells, and microglia and astrocyte reactivity in the substantia nigra pars compacta (SNpc) and striatal dopaminergic fibers.

Methods: The animals were supplemented with fish oil for 50 days and subjected to unilateral intrastriatal 6-hydroxydopamine (6-OHDA)-induced lesions as a model of PD.

Results: Fish oil mitigated the loss of SNpc neurons and nerve terminals in the striatum that was caused by 6-OHDA. This protective effect was associated with reductions of the density of iNOS-immunoreactive cells and microglia and astrocyte reactivity.

Discussion: These results suggest that the antioxidant and antiinflammatory properties of fish oil supplementation are closely related to a decrease in dopaminergic damage that is caused by the 6-OHDA model of PD.  相似文献   

78.
Personal care product use is a potential source of metals exposure among children, but studies have been limited. We measured urinary concentrations of 10 metals (aluminum, arsenic [As], barium [Ba], cadmium, cobalt [Co], lead [Pb], manganese [Mn], molybdenum [Mo], nickel, and zinc [Zn]) in third trimester pregnant women (n?=?212) and their children at 8–14 years of age (n?=?250). Demographic factors (child sex, age, socioeconomic status, and maternal education), body mass index (BMI) z-score, and child personal care product use in the 24?h prior to urine collection were examined as predictors of urinary metal concentrations. Metals were detected in 80–100% of urine samples, with significant differences in maternal versus childhood levels. However, metal concentrations were not strongly correlated within or between time points. In linear regression models including all demographic characteristics, BMI z-score, and specific gravity, age was associated with higher Co (6% [95% CI: 2, 10]), while BMI z-score was associated with lower Mo (-6% [95% CI: -11, -1). In addition, significantly higher metal concentrations were observed among users of colored cosmetics (Mo: 42% [95% CI: 1, 99]), deodorant (Ba: 28% [3, 58]), hair spray/hair gel (Mn: 22% [3, 45]), and other toiletries (As: 50% [9, 108]), as well as with an increasing number of personal care products used (As: 7% [3, 11]) after adjustment for child sex, age, total number of products used, and specific gravity. However, significantly lower metal concentrations were noted for users of hair cream (As and Zn: -20% [-36, -2] and -21% [-35, -2], respectively), shampoo (Pb: -40% [-62, -7]), and other hair products (Pb: -44% [-65, -9]). We found that personal care product use may be a predictor of exposure to multiple metals among children. Further research is recommended to inform product-specific exposure source identification and related child health risk assessment efforts.  相似文献   
79.

Background

The EQ-5D has been frequently used in national health surveys. This study is a head-to-head comparison to assess how expanding the number of levels from three (EQ-5D-3L) to five in the new EQ-5D-5L version has improved its distribution, discriminatory power, and validity in the general population.

Methods

A representative sample (N?=?7554) from the Catalan Health Interview Survey 2011–2012, aged ≥18, answered both EQ-5D versions, and we evaluated the response redistribution and inconsistencies between them. To assess validity of this redistribution, we calculated the mean of the Visual Analogue Scale (VAS), which measures perceived health. The discriminatory power was examined with Shannon Indices, calculated for each dimension separately. Spanish preference value sets were applied to obtain utility indices, examining their distribution with statistics of central tendency and dispersion. We estimated the proportion of individuals reporting the best health state in EQ-5D-5L and EQ-5D-3L within groups of specific chronic conditions and their VAS mean.

Results

A very small reduction in the percentage of individuals with the best health state was observed, from 61.8% in EQ-5D-3L to 60.8% in EQ-5D-5L. In contrast, a large proportion of individuals reporting extreme problems in the 3 L version moved to severe problems (level 4) in the 5 L version, particularly for pain/discomfort (75.5%) and anxiety/depression (66.4%). The average proportion of inconsistencies was 0.9%. The pattern of the perceived health VAS mean confirmed the hypothesis established a priori, supporting the validity of the observed redistribution. Shannon index showed that absolute informativity was higher in the 5 L version for all dimensions. The means (SD) of the Spanish EQ-5D-3L and EQ-5D-5L indices were 0.87 (0.25) and 0.89 (0.22). The proportion of individuals with the best health state within each specific chronic condition was very similar, regardless of the EQ-5D version (≤?30% in half of the 28 chronic conditions).

Conclusion

Although the proportion of individuals with the best possible health state is still very high, our findings support that the increase of levels provided by the EQ-5D-5L contributed to the validity and discriminatory power of this new version to measure health in general population, as in the national health surveys.
  相似文献   
80.

Background

Cervical cancer is one of the most prevalent cancers, but it may be prevented by early detection. Social inequalities in the use of cytology testing have been identified in the literature. However, the degree of income-related inequality has not been quantified and determinants of inequality changes during the economic crisis remain unknown.

Methods

Using the Spanish National Health Surveys (2006–07 / 2011–12), we analyzed how income-related inequalities in the use of cervical cancer screening for women aged 25–64 changed across the economic crisis. We used corrected concentration indices (CCI) which were further decomposed in order to compute the contribution of the explanatory variables. An Oaxaca-type approach was employed to investigate the origin of changes over time.

Results

Our final sample consisted of 10,743 observations in 2006–07 and 6587 in 2011–12. Despite the higher prevalence of screening over time (from 73.9 to 77.9%), pro-rich inequality significantly increased (from CCI?=?0.1726 to CCI?=?0.1880, p <?0.001). Income was the main determinant of inequality in cervical screening, although its contribution decreased over time, as well as the contribution of the type of health insurance, mainly due to changes in elasticity. Other factors, such as nationality or the educational level, seem to have played an important role in the increase of pro-rich inequality of cytology testing.

Conclusions

Reducing cervical screening inequalities would require actions focused on most vulnerable groups such as migrants, low income and low educated population. The implementation of population-based screening programs would also help to cope with income-related inequalities in cytology testing.
  相似文献   
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