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Kamil Torres Anna Torres Grzegorz J. Staśkiewicz Andrzej Chrościcki Tadeusz Łoś Ryszard Maciejewski 《Surgical endoscopy》2009,23(9):2117-2123
Background Surgical procedures enhance production of pro- and anti-inflammatory cytokines and angiogenic factors that play a pivotal
role in the immunological response to surgical trauma and take part in the pathogenesis of tumor growth and adhesions formation.
The purpose of the study was to access the influence of low-pressure CO2 pneumoperitoneum on the inflammatory and angiogenic responses during the postoperative period after laparoscopy.
Methods The study group consisted of 40 patients, operated on due to cholelithiasis using standard-pressure (n = 20) and low-pressure (n = 20) CO2 pneumoperitoneum. Serum concentration of interleukin (IL)-6, IL-8, IL-10, vascular endothelial growth factor (VEGF)-A, and
endostatin were measured before and at 6, 24, and 48 h after surgery with commercially available enzyme-linked immunosorbent
assay (ELISA).
Results Concentrations of IL-6 increased significantly after the operations in both groups. No differences were observed between the
groups in regards to IL-6, IL-8, and IL-10 levels. Concentrations of VEGF-A measured at 6 and 48 h were significantly lower
in patients who underwent laparoscopies performed with low-pressure pneumoperitoneum. No significant variations were observed
in endostatin serum concentration. Concentrations of the studied parameters were not influenced by duration of surgery or
by age, gender, or body mass index (BMI) of the patients.
Conclusions The results obtained in our study do not show any significant differences between studied operative procedures with regards
to systemic inflammatory response. Changes in the concentrations of VEGF-A and endostatin observed in the studied population
may suggest this technique is more favorable with regards to angiogenesis process intensity, along with all its consequences
and implications. 相似文献
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The aim of the study was the investigation of the biochemical condition of elements likely to directly participate in active
closing of the urethral lumen. We estimated glycogenolysis in urinary bladder, perivesical connective tissue and levator ani
muscle (LAM) samples obtained intraoperatively from 80 stress incontinent women. Glycogen content as well as activities of
active and total glycogen phosphorylase and acid exo-1,4-alpha-glucosidase were measured. Material from the urinary bladder
and perivesical connective tissue was insignificantly altered, and glycogen contents in the bladder (2.03±1.38 g/100 g wet
tissue) were considered to be normal. In the LAM glycogenolysis was much more activated than in other tissues (p<0.001 by
Fischer's exact test). Of LAM specimens 78% (22/28) revealed imbalanced biochemistry of glycogen with activation of hydrolytic
decomposition. We conclude that stress urinary incontinence in women is frequently associated with metabolic alterations in
the periurethral striated fibres. This study indirectly supports our recent hypothesis on the pathogenesis of the disease
in terms of muscle fibre type transitions. 相似文献
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Olfactory sensory neurons are trophically dependent on the olfactory bulb for their prolonged survival. 总被引:16,自引:0,他引:16
In most neural systems, developing neurons are trophically dependent on contact with their synaptic target for their survival and for some features of their differentiation. However, in the olfactory system, it is unclear whether or not the survival and differentiation of olfactory sensory neurons depend on contact with the olfactory bulb (normally the sole synaptic target for these neurons). In order to address this issue, we examined neuronal life-span and differentiation in adult rats subjected to unilateral olfactory bulb ablation at least 1 month prior to use. Life-span of a newly generated cohort of olfactory neurons was determined by labeling them at their "birth" via the incorporation of 3H-thymidine. In the absence of the bulb, neurons are continually produced at a twofold greater rate. However, the epithelium on the ablated side is thinner, indicating that average neuronal life-span must be reduced in the targetless epithelium. Indeed, nearly 90% of the labeled neurons disappear from the bulbectomized side between 5 d and 2 weeks of neuronal age. Moreover, on electron microscopic examination, olfactory axons are degenerating in large numbers on the ablated side. Since labeled neurons migrate apically through the width of the epithelium during this same period, it appears that most, if not all, neurons on the ablated side have a life-span on the order of 2 weeks or less. In contrast, there is a more moderate degree of neuronal loss on the unoperated side of the same animals during the first 2 weeks after tracer injection, and that occurs while the neurons are concentrated in the deeper half of the epithelium, suggesting that there is a preexisting population of neurons in the control epithelium that does not die during this period. Likewise, degenerating axons are much less frequent on the unoperated side. We conclude that life-span is significantly shorter for olfactory neurons born in the targetless epithelium and that olfactory neurons are trophically dependent on the presence of the bulb for their prolonged survival. Neuronal differentiation in the absence of the bulb was assessed according to ultrastructural criteria and the pattern of protein expression using antisera to the growth associated protein GAP-43 and the olfactory marker protein. By both measures, most neurons in the epithelium on the bulbectomized side, but not all, are immature.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
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Łaba A Ostrowska A Patrzałek D Paradowski L Lange A 《Archivum immunologiae et therapiae experimentalis》2005,53(5):442-453
INTRODUCTION: The successful use of hepatocytes depends on a reliable demonstration of the functional and morphological integrity of isolated cells. Herein we investigated whether the isolation and cryopreservation of primary human hepatocytes can compromise cell viability and liver-specific characteristics. MATERIAL/METHODS: Hepatocytes were isolated from encapsulated human liver segments by a modified 2-step perfusion technique. Isolated cells were Percoll-purified, cryopreserved, and stored in liquid nitrogen for 1-12 months. For rapid assessment of fresh and cryopreserve/thawed hepatocyte yield and viability, the cells were stained with trypan blue or labeled with fluorochromes. For immunocytochemical analysis, the cells were labeled with monoclonal antibodies for the presence of the following antigens and chemokines: CD3, CD45Ro, CD45Ra, CD34, CD68, CD90, CD95, CD20, HLA-DR, Ki67, PCNA, Bcl-2, p53, CXCR3, CXCR4, and SDF-1. The cells were tested for several specific functions, such as ureagenesis, energy status, MTT activity, lactate dehydrogenase leakage, and total CYP450 content. RESULTS: Assessment of both freshly isolated (Percoll-purified) and cryopreserved/thawed hepatocytes revealed a low constitutive level of contamination by non-parenchymal cells compared with crude (unpurified) preparations and tissue sections. All viable hepatocytes showed intact morphology and retained CYP450 protein, energy status, and urea synthesis. CONCLUSIONS: Modifications in hepatocyte preparations, such as depletion of dead, damaged, and nonparenchymal cells, improves cell purity, which can be adapted to further evaluation of hepatocyte immunogenicity. These data illustrate the importance and feasibility of human hepatocyte banking. 相似文献
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M. Parczewski J. Kordek E. Janczewska A. Pisula W. Łojewski Ł. Socha M. Wawrzynowicz-Syczewska M. Bociąga-Jasik A. Szymczak I. Cielniak E. Siwak E. Mularska B. Aksak-Wąs A. Urbańska N. Lübke 《Clinical microbiology and infection》2019,21(4):513.e1-513.e6
Objectives
The aim of the study was to characterize the differences in the frequencies of NS3 and NS5A resistance-associated variants (RAVs) among Polish therapy-naive genotype 1 (G1) hepatitis C virus (HCV)-monoinfected and human immunodeficiency virus (HIV)/HCV-coinfected patients including clustering patterns and association of RAV frequency with liver fibrosis.Methods
NS3/NS5A RAVs were identified by population sequencing in 387 directly acting antiviral treatment-naive G1-infected individuals (54 with genotype 1a (G1a) and 333 with genotype 1b (G1b)). Liver fibrosis was assessed based on histopathology or ultrasound elastography. Phylogenetic clusters were identified using maximum likelihood models. For statistics, chi-squared or two-sided Fisher's exact tests and multivariate logistic regression models were used, as appropriate.Results
NS3 RAVs were found in 33.33% (18/54) for G1a and 2.62% (8/297) for G1b whereas NS5A variants were present in 5.55% (3/54) G1a and 9.31% (31/333) G1b sequences. Variations in NS5A 31 and 93 codon positions were found only in G1b (4.2% (14/333) for L31I/F/M and 5.39% (17/333) for Y93H). NS5A RAVs were more frequent among patients with advanced liver fibrosis (17.17% (17/99) for F3–F4 versus 6.94% (17/245) for F0–F2; p 0.004) or liver cirrhosis (20.34% (12/59) for F4 versus 7.72% (22/285) for F0–F3; p 0.003). Liver cirrhosis (F4) was associated with higher odds ratio of the NS5A RAVs among HCV-infected patients (odds ratio 2.34, 95% CI 1.004–5.291; p 0.049). NS5A RAVs were less frequent among sequences forming clusters and pairs (5.16% (8/155) versus 11.21% (26/232); p 0.039).Conclusions
Presence of NS5A RAVs correlated with progression of liver fibrosis and represents de novo selection of variants rather than transmission of drug resistance. Hence, the presence of NS5A RAVs may be a predictor for a long-lasting HCV infection. 相似文献10.
Łuszczek W Kubicka W Cislo M Nockowski P Mańczak M Woszczek G Baran E Kuśnierczyk P 《Immunology letters》2003,85(1):59-64
Association of psoriasis vulgaris with HLA-C is not equally strong in different human populations. It has not yet been studied in Polish patients at DNA level, but only by serology that is inadequate for HLA-C. Therefore, we examined the distribution of HLA-C alleles by means of low resolution PCR-SSP in 102 Polish psoriatics and 123 healthy controls. We have found significantly higher representation of HLA-Cw*06 (odds ratio, 18.73; P(cor)<0.001) and significantly lower representation of HLA-Cw*07 (odds ratio, 0.41; P(cor)<0.038) in patients than in controls. Association of HLA-Cw*06 with psoriasis was even stronger in early age at onset (0-20 years) group: odds ratio, 77.71; P(cor)<0.001. Therefore, our population seems to belong to those with strong association of psoriasis with HLA-Cw*06. 相似文献