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1.
The current literature suggests that the antibacterial effect of leukocyte- and platelet-rich plasma (L-PRP) is directly related to platelet and leukocyte concentrations. The aim of this study was twofold: first, to evaluate the antimicrobial effect of L-PRP against selected bacterial strains in vitro, and second, to correlate this effect with leukocyte and platelet content in the final concentration. Blood was collected from 20 healthy males, and L-PRP, acellular plasma (AP), and autologous thrombin were consecutively prepared. Flow cytometry analysis of the blood, L-PRP, and AP was performed. The L-PRP gel, liquid L-PRP, and thrombin samples were tested in vitro for their antibacterial properties against seven selected bacterial strains using the Kirby–Bauer disk-diffusion method. There was notable antimicrobial activity against selected bacterial strains. No statistically significant correlations between antimicrobial activities and the platelet concentration in L-PRP were observed. Statistically significant positive correlations between selected leukocyte subtypes and antimicrobial activity were noted. A negative correlation was found between elevated monocyte count and antimicrobial activity of L-PRP against one bacterial strain studied. L-PRP possesses antimicrobial activity and can be potentially useful in the fight against certain postoperative infections. The bactericidal effect of L-PRP is caused by leukocytes, and there exists a relationship among selected leukocyte subtypes and L-PRP antimicrobial activity.  相似文献   
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In this paper, an antimycobacterial component of extracellular metabolites of a gut bacterium Raoultella ornithinolytica from D. veneta earthworms was isolated and its antimycobacterial action was tested using Mycobacterium smegmatis. After incubation with the complex obtained, formation of pores and furrows in cell walls was observed using microscopic techniques. The cells lost their shape, stuck together and formed clusters. Surface‐enhanced Raman spectroscopy analysis showed that, after incubation, the complex was attached to the cell walls of the Mycobacterium. Analyses of the component performed with Fourier transform infrared spectroscopy demonstrated high similarity to a bacteriocin nisin, but energy dispersive X‐ray spectroscopy analysis revealed differences in the elemental composition of this antimicrobial peptide. The component with antimycobacterial activity was identified using mass spectrometry techniques as a glycolipid–peptide complex. As it exhibits no cytotoxicity on normal human fibroblasts, the glycolipid–peptide complex appears to be a promising compound for investigations of its activity against pathogenic mycobacteria.  相似文献   
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Parasitology Research - Sparganosis is a zoonosis caused by the spargana (larvae) of Spirometra sp. (Diphyllobothriidae). Reptiles are particularly important vectors for the transmission of this...  相似文献   
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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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International Journal of Legal Medicine - It is extremely rare for table salt to be used to preserve a dead body in criminal cases. In the case presented here, after the death of his 85-year-old...  相似文献   
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Somatic mosaicism for DNA copy‐number alterations (SMC‐CNAs) is defined as gain or loss of chromosomal segments in somatic cells within a single organism. As cells harboring SMC‐CNAs can undergo clonal expansion, it has been proposed that SMC‐CNAs may contribute to the predisposition of these cells to genetic disease including cancer. Herein, the gross genomic alterations (>500 kbp) were characterized in uninvolved mammary glandular tissue from 59 breast cancer patients and matched samples of primary tumors and lymph node metastases. Array‐based comparative genomic hybridization showed 10% (6/59) of patients harbored one to 359 large SMC‐CNAs (mean: 1,328 kbp; median: 961 kbp) in a substantial portion of glandular tissue cells, distal from the primary tumor site. SMC‐CNAs were partially recurrent in tumors, albeit with considerable contribution of stochastic SMC‐CNAs indicating genomic destabilization. Targeted resequencing of 301 known predisposition and somatic driver loci revealed mutations and rare variants in genes related to maintenance of genomic integrity: BRCA1 (p.Gln1756Profs*74, p.Arg504Cys), BRCA2 (p.Asn3124Ile), NCOR1 (p.Pro1570Glnfs*45), PALB2 (p.Ser500Pro), and TP53 (p.Arg306*). Co‐occurrence of gross SMC‐CNAs along with point mutations or rare variants in genes responsible for safeguarding genomic integrity highlights the temporal and spatial neoplastic potential of uninvolved glandular tissue in breast cancer patients.  相似文献   
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Aspirin-induced asthma (AIA) is a distinct clinical syndrome characterized by severe asthma exacerbations after ingestion of aspirin or other non-steroidal anti-inflammatory drugs. The exact pathomechanism of AIA remains unknown, though ongoing research has shed some light. Recently, more and more attention has been focused on the role of aspirin in the induction of oxidative stress, especially in cancer cell systems. However, it has not excluded the similar action of aspirin in other inflammatory disorders such as asthma. Moreover, increased levels of 8-isoprostanes, reliable biomarkers of oxidative stress in expired breath condensate in steroid-naïve patients with AIA compared to AIA patients treated with steroids and healthy volunteers, has been observed. This review is an attempt to cover aspirin-induced oxidative stress action in AIA and to suggest a possible related pathomechanism.  相似文献   
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