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41.
42.
Antiulcer properties of a synthetic anxiolytic Selank and in vivo formed metabolites of this compound were studied on 3 experimental models of ulceration. The test peptides decreased the area of experimental gastric ulcers. __________ Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 143, No. 1, pp. 57–59, January, 2007  相似文献   
43.

Brain invasion has not been recognized as a standalone criterion for atypical meningioma by the WHO classification until 2016. Since the 2007 edition suggested that meningiomas harboring brain invasion could be classified as grade 2, brain invasion study was progressively strengthened in our center, based on a strong collaboration between neurosurgeons and neuropathologists regarding sample orientation and examination. Practice changes were considered homogeneous enough in 2011. The aim of the present study was to evaluate the impact of gross practice change on the clinical and pathological characteristics of intracranial meningiomas classified as grade 2.

The characteristics of consecutive patients with a grade 2 meningioma surgically managed before (1998–2005, n?=?125, group A) and after (2011–2014, n?=?166, group B) practices changed were retrospectively reviewed.

Sociodemographical and clinical parameters were comparable in groups A and B, and the median age was 62 years in both groups (p?=?0.18). The 5-year recurrence rates (23.2% vs 29.5%, p?=?0.23) were similar. In group A, brain invasion was present in 48/125 (38.4%) cases and was more frequent than in group B (14/166, 8.4%, p?<?0.001). In group A, 33 (26.4%) meningiomas were classified as grade 2 solely based on brain invasion (group ASBI), and 92 harbored other grade 2 criteria (group AOCA). Group ASBI meningiomas had a similar median progression-free survival compared to groups AOCA (68 vs 80 months, p?=?0.24) and to AOCA and B pooled together (n?=?258, 68 vs 90 months, p?=?0.42).

An accurate assessment of brain invasion is mandatory as brain invasion is a strong predictor of meningioma progression.

  相似文献   
44.
Freshly prepared ZnO nanoparticles were incorporated into a chitosan solution in weight ratios ranging from 1:1 to 12:1. Starting from the ratio of 3:1 the chitosan solution was transformed into a gel with a high consistency, which incorporates 15 mL water for only 0.1 g solid substance. The powders obtained after drying the gel were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and thermal analysis (TG-DSC). The electronic (UV–vis), infrared (FTIR) and photoluminescence (PL) spectra were also recorded. ZnO particles were coated with gentamicin and incorporated into the chitosan matrix, to yield a ZnO/gentamicin–chitosan gel. The release rate of gentamicin was monitored photometrically. This ZnO/gentamicin–chitosan gel proved great antimicrobial properties, inhibiting Staphylococcus aureus and Pseudomonas aeruginosa growth in both planktonic and surface-attached conditions. The results indicate that the obtained composite can be used in cutaneous healing for developing improved wound dressings, which combine the antibacterial activity of all three components with the controlled release of the antibiotic. This wound dressing maintains a moist environment at the wound interface, providing a cooling sensation and soothing effect, while slowly releasing the antibiotic. The system is fully scalable to any other soluble drug, as the entire solution remains trapped in the ZnO–chitosan gel.  相似文献   
45.
In this paper, we report the synthesis, characterization (FT-IR, XRD, BET, HR-TEM) and bioevaluation of a novel γ-aminobutiric acid/silica (noted GABA-SiO2 or γ-SiO2) hybrid nanostructure, for the improved release of topical antibiotics, used in the treatment of Staphylococcus aureus infections. GABA-SiO2 showed IR bands which were assigned to Si–O–Si (stretch mode). The XRD pattern showed a broad peak in the range of 18–30° (2θ), indicating an amorphous structure. Based on the BET analysis, estimations about surface area (438.14 m2/g) and pore diameters (4.76 nm) were done. TEM observation reveals that the prepared structure presented homogeneity and an average size of particles not exceeding 10 nm. The prepared nanostructure has significantly improved the anti-staphylococcal activity of bacitracin and kanamycin sulfate, as demonstrated by the drastic decrease of the minimal inhibitory concentration of the respective antibiotics loaded in the GABA-SiO2 nanostructure. These results, correlated with the high biocompatibility of this porous structure, are highlighting the possibility of using this carrier for the local delivery of the antimicrobial substances in lower active doses, thus reducing their cytotoxicity and side-effects.  相似文献   
46.
Zinc oxide (ZnO) nanoparticles (NPs) have been investigated for various skin therapies in recent years. These NPs can improve the healing and modulate inflammation in the wounds, but the mechanisms involved in such changes are yet to be known. In this study, we have designed a facile ZnO nano-coated dressing with improved antimicrobial efficiency against typical wound pathogens involved in biofilm and chronic infections. ZnO NPs were obtained by hydrothermal method and characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and Fourier-transform infrared spectroscopy. Antibacterial and antibiofilm effects were evaluated against laboratory and clinical isolates of significant Gram-negative (Pseudomonas aeruginosa and Escherichia coli) and Gram-positive (Staphylococcus aureus and Enterococcus faecalis) opportunistic pathogens, by quantitative methods. Our results have shown that the developed dressings have a high antibacterial efficiency after 6–24 h of contact when containing 0.6 and 0.9% ZnO NPs and this effect is similar against reference and clinical isolates. Moreover, biofilm development is significantly impaired for up to three days of contact, depending on the NPs load and microbial species. These results show that ZnO-coated dressings prevent biofilm development of main wound pathogens and represent efficient candidates for developing bioactive dressings to fight chronic wounds.  相似文献   
47.
48.
Eleven microsatellite markers were developed for the leafhoppers of the genus Aphrodes using shotgun pyrosequencing and will be used to study the genetic diversity, population structure and gene flow within and between species in this genus in order to assess their conservation status. The number of alleles per locus ranged from 3 to 10, while observed and expected heterozygosity values varied from 0.421–1.000 to 0.542–0.876, respectively. Cross-species amplification was successful among the four congeners.  相似文献   
49.
The aim of this multi-center retrospective study was to evaluate the incidence of hyperprogressive disease (HPD) after second-line treatment with pembrolizumab in patients (n = 167) with metastatic non-small-cell lung cancer (NSCLC) whose tumors expressed programmed cell death ligand 1 (PD-L1) in ≥ 1% and to search for hematological and imaging biomarkers associated with its development. Prior to chemotherapy, neutrophil : lymphocyte ratio (NLR1) and platelet : lymphocyte ratio (PLR1), and prior to immunotherapy, NLR2 and PLR2 were retrospectively analyzed. The psoas major muscle area (PMMA) was calculated at the L3 position on computed tomography before chemotherapy (PMMA1) and before immunotherapy (PMMA2) (n = 112). Patients with ∆PMMA (1-PMMA2/PMMA1) × 100 ≥ 10% were considered to have sarcopenia (low muscle mass). After treatment with pembrolizumab on the first computerized tomography (CT) scan evaluation, patients were subdivided as follows as: hyperprogressors (HPs), progressors (Ps), non-progressors (NPs) and pseudoprogressors (PPs). HPs had significantly higher ∆PMMA levels, NLR2 and PLR2 than the other patients. Moreover, in multinomial logistic regression analysis, higher levels of ∆PMMA were associated with a decreased likelihood of being a P [odds ratio (OR) = 0·81; 95% confidence interval (CI) = 0·65–0·99; P = 0·047] or an NP (OR = 0·76; 95% CI = 0·62–0·94; P = 0·012) versus an HP. Higher NLRs tended to decrease the likelihood of being a P versus an HP (OR = 0·66; 95% CI = 0·42–1·06; P = 0·09) and significantly decreased the likelihood of being an NP versus an HP (OR = 0·44; 95% CI = 0·28–0·69; P < 0·0001). Our data suggest that a high pre-immunotherapy NLR2 and the presence of sarcopenia are potential risk factors for the development of HPD.  相似文献   
50.

Background

Cerebral vasculopathy is a serious complication of sickle cell anemia. Overt strokes are largely due to intracranial arteriopathy, detected by routine transcranial Doppler and largely prevented through chronic transfusions. As extracranial internal carotid artery arteriopathy was considered rare, it has not been routinely assessed in sickle cell anemia. Recent cases of overt strokes associated with stenosis/occlusion of the extracranial portion of the internal carotid artery prompted us to include extracranial internal carotid artery assessment to our transcranial Doppler sonography protocol.

Objective

The aim of the study was to perform a cross-sectional study in children with sickle cell anemia to evaluate Doppler flow patterns of the extracranial internal carotid arteries and to assess potential associated factors.

Materials and methods

Between June 2011 and April 2012, 435 consecutive stroke-free children with sickle cell anemia (200/235 M/F, median age: 7.9 years) were assessed for extracranial internal carotid artery using a 2-MHz transcranial Doppler sonography probe via a submandibular window during routine transcranial Doppler sonography visits. The course of both extracranial internal carotid artery was assessed by color Doppler mapping, and the highest flow velocity was recorded after insonation of the entire length of the artery and analyzed. Intra- and extracranial MR angiographies were available in 104/435 subjects for comparison.

Results

Mean (SD) extracranial internal carotid artery time-averaged mean of maximum velocity was 96 (40) cm/s. Extracranial internal carotid artery tortuosities were echo-detected in 25% cases and were more frequent in boys (33% vs.18%; P?<?0.001). Velocity ≥160 cm/s in at least one extracranial internal carotid artery was found in 45 out of 435 patients with sickle cell anemia (10.3%) and was highly predictive of MR angiography stenosis. Simultaneous abnormal intracranial velocity (≥200 cm/s) was recorded in 5/45 patients, while 40 patients had isolated extracranial internal carotid artery velocity ≥160 cm/s. Low hemoglobin (odds ratio: 1.9/g/dL, 95% confidence interval (CI): 1.3–2.9; P?=?0.001) and tortuosities (odds ratio: 19.2, 95% CI: 7.1–52.6; P?<?0.001) were significant and independent associated factors for isolated extracranial internal carotid artery velocities ≥160 cm/s.

Conclusion

Adding extracranial internal carotid artery evaluation via the submandibular window to transcranial Doppler sonograpy allowed us to detect 10.3% patients at risk for extracranial internal carotid arteriopathy. Further studies are needed to evaluate the prognosis of these anomalies.  相似文献   
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