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1.

Background

The complex pathophysiological events occurring after traumatic spinal cord injuries (TSCI) make this devastating trauma still incurable. Peptide amphiphile (PA) hydrogels are nanobiomaterials displaying desirable properties for application in regenerative medicine because they are absorbable, injectable, allowing biofunctionalization, controlling release of trophic factors and mimic extracellular matrix (ECM). In this study, we explored the potentiality of the IKVAV-functionalized PA hydrogel to provide a permissive environment for cell migration and growth as well as sustained release of BDNF at the lesion after severe compression injury model.

Methods

The IKVAV-functionalized PA was synthesized by automated solid-phase approach and its secondary structure was evaluated by Circular dichroism (CD) spectroscopy. The potential of IKVAV-functionalized PA to self-assemble into nanofibers and hydrogel formation were assessed using transmission electron microscopy (TEM). Release profiles of BDNF from hydrogel and the bioactivity of the released BDNF from hydrogel were determined using ELISA and DRG bioassay, respectively. Severe spinal cord injury was induced using clip compression at T7-T8 vertebral segment. Twenty four hours post-injury the animals were treated by either IKVAV PA hydrogel, BDNF-loaded IKVAV PA hydrogel, BDNF solution or saline. Two and six weeks later, animals were sacrificed and the lesion site was evaluated based on GFAP, CD68 and ß III tubulin immunoreactivity. Also, locomotor recovery was assessed during 6 weeks using Basso, Beattie, Bresnahan (BBB) scoring test.

Results

The IKVAV PA arranged into nanofibrous structure and provided a sustained release of BDNF over 21 days while preserved the bioactivity of BDNF. Also, BDNF loading influenced the hydrogel nanostructure resulting in aligned orientation of nanofibers. Injection of BDNF-loaded IKVAV PA hydrogel resulted in a considerable axon preservation and astrogliosis reduction at 6 weeks post-injury without showing any inflammatory reaction. However, the BBB score was not statistically different between different treatment groups.

Conclusion

Although the locomotor functional recovery was not observed in this study, the axon preservation and minimal inflammation in animals treated with BDNF-incorporated hydrogel indicate the potentiality of the designed intervention for further evaluations in the path of developing efficient therapies for severe spinal cord injury.  相似文献   
2.
Purpose

To gain insight into current research regarding prehospital care (PHC) in patients with potential traumatic spinal cord injury (TSCI) and to disseminate the findings to the research community.

Methods

In March 2019, we performed a literature search of publications from January 1990 to March 2019 indexed in PubMed, gray literature including professional websites; and reference sections of selected articles for other relevant literature. This review was performed according to Arksey and O’Malley’s framework.

Results

There were 42 studies selected based on the inclusion criteria for review; 18 articles regarding immobilization; 12 articles regarding movement, positioning and transport; four for spinal clearance; three for airway protection; and two for the role of PHC providers. There were some articles that covered two topics: one article was regarding movement, positioning and transport and airway protection, and two were regarding spinal clearance and the role of PHC providers.

Conclusion

There was no uniform opinion about spinal immobilization of patients with suspected TSCI. The novel lateral trauma position and one of two High Arm IN Endangered Spine (HAINES) methods are preferred methods for unconscious patients. Controlled self-extrication for patients with stable hemodynamic status is recommended. Early and proper identifying of potential TSCI by PHC providers can significantly improve patients’ outcomes and can result in avoiding unwanted spinal immobilization. Future prospective studies with a large sample size in real-life settings are needed to provide clear and evidence-based data in PHC of patients with suspected TSCI.

  相似文献   
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4.
BACKGROUND: Acetaminophen was falsely detected in the plasma of a severely jaundiced patient, and a methodologic interference from bilirubin was suspected. METHODS: Acetaminophen was measured by an enzymatic method (GDS Diagnostics). The putative bilirubin interference was investigated in 12 hyperbilirubinemic specimens and in bilirubin linearity calibrators. The analytical method was modified to correct for background absorbance at a second wavelength. Hyperbilirubinemic specimens were fortified with acetaminophen to assess the effect of the interference on acetaminophen measurements. RESULTS: Acetaminophen was detected in 12 specimens from hyperbilirubinemic patients without a history of recent acetaminophen exposure. Dilution of hyperbilirubinemic specimens produced a nonproportional decrease in apparent acetaminophen concentrations, and no acetaminophen was detected when bilirubin was <50 mg/L. Background correction at a second wavelength failed to compensate for the interference. Although erroneous acetaminophen concentrations were detected in all specimens with high bilirubin, acetaminophen measurements in fortified specimens were accurate. CONCLUSION: The data are consistent with bilirubin interference in the enzymatic and/or chromogenic reactions involved in the acetaminophen method.  相似文献   
5.
Background: Nonrandomized response (NRR) models are a new generation of surveys for sensitive issues. This study aims to evaluate the validity of estimates from the crosswise model (as one of the efficient models) through employing different response probabilities of nonsensitive questions. Methods: This cross-sectional study was conducted during October and November 2015 among 1777 students of Tabriz University of Medical Sciences. Estimates of monthly alcohol consumption, and at least one instance of illicit drug use and extramarital sex over the last year were determined using direct questioning (DQ) and the Crosswise model (CM). In the last model, the probability of positive response to the nonsensitive questions was determined by using five different methods: uniform distribution (I), Benford’s law (II), and estimations based on data from three other studies (III, IV, V). Results: Crosswise estimates of sensitive behaviors with different probabilities of a positive response to nonsensitive questions differed significantly. For example, estimates of history of using illegal opioids at least once in the last year among men varied significantly from 5.0% to 16.1% with different crosswise models based on the probability of being born in Spring using method I (0.250), III (0.287), IV (0.248), and V (0.310). The model based on Benford’s law (II) was applied to estimate alcohol and cannabis consumption, and its estimates showed significant discrepancy with results of crosswise models I and V. Conclusion: Estimates from crosswise model is highly sensitive to the response probability of nonsensitive questions. It seems that if this question is not selected carefully, the mentioned models will provide overestimates or underestimates, and the more-is-better hypothesis is not always valid. To achieve valid estimates, the exact probability of a positive response to the nonsensitive question must be known for the studied population.  相似文献   
6.
Cholinergic neurotransmission in the central and autonomic nervous systems regulates immediate variations in and longer-term maintenance of cardiovascular function with acetylcholinesterase (AChE) activity that is critical to temporal responsiveness. Butyrylcholinesterase (BChE), largely confined to the liver and plasma, subserves metabolic functions. AChE and BChE are found in hematopoietic cells and plasma, enabling one to correlate enzyme levels in whole blood with hereditary traits in twins. Using both twin and unrelated subjects, we found certain single nucleotide polymorphisms (SNPs) in the ACHE gene correlated with catalytic properties and general cardiovascular functions. SNP discovery from ACHE resequencing identified 19 SNPs: 7 coding SNPs (cSNPs), of which 4 are nonsynonymous, and 12 SNPs in untranslated regions, of which 3 are in a conserved sequence of an upstream intron. Both AChE and BChE activity traits in blood were heritable: AChE at 48.8 ± 6.1% and BChE at 81.4 ± 2.8%. Allelic and haplotype variations in the ACHE and BCHE genes were associated with changes in blood AChE and BChE activities. AChE activity was associated with BP status and SBP, whereas BChE activity was associated with features of the metabolic syndrome (especially body weight and BMI). Gene products from cDNAs with nonsynonymous cSNPs were expressed and purified. Protein expression of ACHE nonsynonymous variant D134H (SNP6) is impaired: this variant shows compromised stability and altered rates of organophosphate inhibition and oxime-assisted reactivation. A substantial fraction of the D134H instability could be reversed in the D134H/R136Q mutant. Hence, common genetic variations at ACHE and BCHE loci were associated with changes in corresponding enzymatic activities in blood.  相似文献   
7.
In research outputs both quality and quantity are of critical value and evaluation of both aspects is required for best evaluation. Several studies have worked on single or two-dimensional methods that provide the assessment of quality, quantity or both simultaneously in different branches of sciences, but none of them have played a role in a particular area of medicine. This study has been conducted to compare countries worldwide in the field of medical researches. Measuring both quality and quantity of researches is performed separately. In order to evaluate countries from both aspects of quantity and quality of research outputs, a modified form of the citation per publication (CPPm) and publication per population (PPPm) were used to make these indices comparable through different years and nations by normalizing the values according to the world average standards. When countries are ranked by CPPm, Iceland ranks the 1st with the score of 1.98, Faroe Islands and Gambia rank the 2nd and the 3rd with scores of 1.84 and 1.63, respectively. In PPPm Switzerland, Sweden and Denmark ranked the top three with scores of 13.34, 11.67 and 10.32, respectively. Iran ranked 71 in CPPm and 141 in PPPm. Ranking countries makes it possible to identify countries which have performed better in research outcomes by means of quality and quantity; thus, reforming policies can be taken into action to lower the waste of money, higher quality and quantity of outputs while providing helpful tip(s) for institutions to improve.  相似文献   
8.
Spinal cord injured (SCI) patients have sexual disorders including erectile dysfunction (ED), impotence, priapism, ejaculatory dysfunction and infertility. Treatments for erectile dysfunction include four steps. Step 1 involves smoking cessation, weight loss, and increasing physical activity. Step 2 is phosphodiesterase type 5 inhibitors (PDE5I) such as Sildenafil (Viagra), intracavernous injections of Papaverine or prostaglandins, and vacuum constriction devices. Step 3 is a penile prosthesis, and Step 4 is sacral neuromodulation (SNM). Priapism can be resolved spontaneously if there is no ischemia found on blood gas measurement or by Phenylephrine. For anejaculatory dysfunction, massage, vibrator, electrical stimulation and direct surgical biopsy can be used to obtain sperm which can then be used for intra-uterine or in-vitro fertilization. Infertility treatment in male SCI patients involves a combination of the above treatments for erectile and anejaculatory dysfunctions. The basic approach to and management of sexual dysfunction in female SCI patients are similar as for men but do not require treatment for erectile or ejaculatory problems.  相似文献   
9.
Objective: Injury is a major cause of morbidity and mortality in the world.The assessment of patterns and severity of injury in high-risk groups is crucial for planning and service development.On a lar...  相似文献   
10.
This study aimed to assess correlations between anti-malarial antibody levels and differences in malariometric characteristics, seen between two sympatric ethnic groups, the Fulani and the Dogon, living in Mali. Plasma levels of anti-malarial IgE, IgG, IgG1-4 and total IgE were determined in asymptomatic individuals, of the above mentioned groups, and were correlated to malariometric indexes. Significantly higher levels of anti-malarial IgE, IgG, IgG1-3 and total IgE were detected in the Fulani individuals as compared to the Dogon. No difference in plasma levels of malaria specific IgG4 was noted between the two groups. Within the Fulani, an increase in total IgE levels was associated with the presence of infection. As the IgG4 level increased, the number of clones decreased in the Fulani individuals. A positive correlation between elevated levels of anti-malarial IgG and IgG3 and splenomegaly was noted only within the Fulani group. No other correlations between antibody levels and parasite prevalence, clone numbers or spleen rates were observed in any of the communities. These results suggest that the magnitude of antibody response against Plasmodium falciparum may not be as important as it is believed to be. Instead, the fine specificity or function of the response might be more critical in protection against malaria disease.  相似文献   
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