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11.

Background

Inflammasomes regulate activation of caspase-1, which cleaves and activates interleukin (IL)-1β and IL-18, the cytokines that trigger pro-inflammatory and antimicrobial responses. There is very little known about inflammasome function in the subsets of monocytes (MO) isolated from preterm neonates born extremely and very prematurely.

Methods

A group of 76 very low birth weight patients without early-onset sepsis was divided into extremely preterm (<28 gestational week) or very preterm (28–32 gestational week) neonates. The first blood sample was collected on the 5th day of life (5th DOL) to analyse MO subsets as well as the intracellular IL-1β expression and supernatant concentration of IL-1β and IL-18. Secondary blood samples were collected within 24 h of late-onset sepsis (LOS) development and analysed as above.

Results

On the 5th DOL, the extremely preterm neonates were characterized by a significantly higher absolute count of MO, in particular in the classical and intermediate subsets, as compared to the very preterm group. The counts of the intermediate and non-classical MO subsets increased during LOS in all neonates. We did not observe significant differences in the intracellular IL-1β expression between the analysed groups. Furthermore, the levels of the analysed cytokines in the MO supernatants were comparable between the extremely and very preterm neonates on the 5th DOL. Finally, a higher level of IL-18 was observed in the supernatant of the extremely preterm group during LOS.

Conclusions

During LOS, extremely preterm neonates excrete a higher level of IL-18 cytokines compared to very preterm neonates. Further studies are required to determine whether this observation is a result of a higher count of the circulating MO or is a true reflection of increased inflammasome function in this particular group of newborns.  相似文献   
12.

Purpose

Nonhealing wounds or skin ulcerations are the result of insufficient repair and destruction of a local healing potential. Opportunistic infections which cause a lot of ulcer complications influence the worsening general condition of patients with AIDS, ultimately leading to death. The chronicity of the condition and poor results of conventional therapy have prompted the search for new methods of treatment.

Materials and methods

We have examined venous or arteriovenous insufficiency-related extensive crural ulcers in AIDS patients. Crural ulcer healing processes were evaluated with clinical observations and histopathological, immunohistochemical and molecular examinations of tissue samples harvested from the wound edges before and on day 10 after L-PRP cover dressing.

Results

Clinical observations showed positive effects of L-PRP in all patients. However, complete wound closure was noted in 60% of cases. Statistical analysis of histological examination showed increased epidermal processes between samples, but the difference was nonsignificant. However, immunohistochemical investigations showed an increased healing process with strong statistical significance. The mean VEGF level before L-PRP usage was 114.3 vessels/mm2 and on day 10 118.9 (p = 0.001523). The mean FLK level was 103.2 and 109.9 respectively (p = 0.008241). The biggest differences were observed for CD34, with values of 68.2 on day 0 and 100.8 on day 10 (p = 0.006982). Molecular analysis generally showed decreased gene expression and confirmed vascular formation and reepithelialization processes.

Conclusions

In our opinion, L-PRP may be used to eradicate microorganisms from wounds, to induce neovascularization, and in unhealed cases prepare the base and edge of the ulcer for skin grafting and tissue expansion procedures.  相似文献   
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Cathelicidin LL-37 is one of the few human bactericidal peptides with potent antistaphylococcal activity. In this study we examined the susceptibility of LL-37 to proteolytic degradation by two major proteinases produced by Staphylococcus aureus, a metalloproteinase (aureolysin) and a glutamylendopeptidase (V8 protease). We found that aureolysin cleaved and inactivated LL-37 in a time- and concentration-dependent manner. Analysis of the generated fragments by mass spectroscopy revealed that the initial cleavage of LL-37 by aureolysin occurred between the Arg19-Ile20, Arg23-Ile24, and Leu31-Val32 peptide bonds, instantly annihilating the antibacterial activity of LL-37. In contrast, the V8 proteinase hydrolyzed efficiently only the Glu16-Phe17 peptide bond, rendering the C-terminal fragment refractory to further degradation. This fragment (termed LL-17-37) displayed antibacterial activity against S. aureus at a molar level similar to that of the full-length LL-37 peptide, indicating that the antibacterial activity of LL-37 resides in the C-terminal region. In keeping with LL-37 degradation by aureolysin, S. aureus strains that produce significant amounts of this metalloprotease were found to be less susceptible to LL-17-37 than strains expressing no aureolysin activity. Taken together, these data suggest that aureolysin production by S. aureus contributes to the resistance of this pathogen to the innate immune system of humans mediated by LL-37.  相似文献   
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OBJECTIVE: The aim of this study was to determine whether liver transplantation of patients with antiphospholipid antibodies (APA) is 1) adversely affected with vascular thrombosis and 2) whether such antibodies persist post transplantation. METHODS: Twelve patients with APA awaiting transplant were identified and characterized biochemically and immunologically. Each had the level of APA determined using commercially available enzyme-linked immunoassay kits before, during, and after liver transplantation. RESULTS: No patient in this series experienced a transplant-related vascular thrombosis. The titer of APA fell to levels at or below those present in normals and remained low in two of 12 or undetectable in 10 of 12 patients 1 yr after liver transplantation. CONCLUSIONS: We reached the following conclusions: 1) Antiphospholipid positivity does not identify patients at high risk for post-transplant vascular thrombosis. 2) The levels of antiphospholipid present in sera pretransplant fell during transplantation and remained low or undetectable 1 month and 1 yr post transplantation.  相似文献   
19.
Population studies indicate a strong relationship between birth weight (BW) and body size in later life. However, BW as a variable was never accounted for in studies on the relationship between attention-deficit/hyperactivity disorder (ADHD) and overweight. This study aims to assess the relationship between ADHD and overweight with control of birth weight and other confounding factors. Prevalence of overweight was compared in clinical sample of 219 boys with ADHD and 396 boys without ADHD, aged 6–18 years. The following factors were controlled: BW, parents income and education level, place of residence, ADHD type, selected comorbid disorders and stimulant treatment. Overweight and obesity were diagnosed according to the criteria proposed by the International Obesity Task Force. Logistic regression analysis was used to estimate the association between ADHD and the prevalence of overweight and obesity. Boys with ADHD differed significantly from the control group in distribution of low BW (8.2 vs. 3.0 %, χ 2 = 8.23, p = 0.02). Low BW was associated with a lower prevalence of overweight than normal and high BW (0 vs. 12.14 %, χ 2 = 4.12, p = 0.04). Overweight was observed significantly more often in boys with ADHD (17.3 vs. 8.3 %, χ 2 = 11.23, p < 0.001) even after adjustment for BW and other variables (OR = 2.44, 95 % CI 1.38–4.29, p = 0.002) and after controlling for ADHD type, stimulant treatment and selected comorbid disorders. Independently to applied analysis, obesity was not associated with ADHD. Lower birth weight is over twice more often observed in boys with ADHD than in control group. Although this phenomenon may reduce the rate of overweight in the studied group, ADHD remains strongly associated with increased prevalence of overweight.  相似文献   
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