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81.
Placenta from an extrauterine abdominal pregnancy was examined after a 37-week healthy infant gestation. The placenta, with its fetal surface down and maternal surface up, protruded from the pelvic area to peritoneal cavity in the wall of the amniotic sac containing fetus. The placenta was implanted under the thin subperitoneal layer of maternal tissue completely covered by peritoneal serosa and was formed by several small lobes connected by intramembranous placental vessels. Insertion of the trivascular umbilical cord was velamentous. Partially remodeled arteries infiltrated by intermediate trophoblast and frequent veins directly communicating with the placental intervillous space were identified in the subperitoneal maternal tissue. The term "placenta accreta" is appropriate in this case because villi in the basal plate implanted directly in the maternal subserosal connective tissue without intervening decidua.  相似文献   
82.
The pathogenesis of age-related macular degeneration (AMD) is thought to be determined by an array of environmental and genetic factors. The association of increased expression of vascular endothelial growth factor (VEGF) with AMD, especially the wet form of AMD, was reported in several studies. The VEGF gene is highly polymorphic and some of its polymorphisms may affect its expression. In our work, we searched for an association between the −460C> (rs833061) and −634G>C (rs2010963) polymorphisms of the VEGF gene and the occurrence of AMD and its dry and wet forms. We have chosen these polymorphisms because they were shown to be significant in other studies and we previously showed their association with diabetic retinopathy. A total of 401 individuals were enrolled in this study: 136 controls, and 88 patients with dry and 177 with wet AMD. The polymorphisms were determined with DNA from peripheral blood lymphocytes by allele-specific and restriction fragment length polymorphism polymerase chain reaction. The significance of the polymorphisms was assessed by multiple logistic regression, producing odds ratios (ORs) and 95% confidence intervals (CIs). We observed a weak association (OR 2.90) between AMD occurrence and the C/T genotype of the −460C>T polymorphism. An association (OR 3.77) between the C/T genotype of the −460C>T polymorphism and the occurrence of dry AMD was observed. The T/T genotype considerably lowered the risk of dry AMD (OR 0.19). Dry AMD was associated with the C/C genotype of the −634G>C polymorphism (OR 3.68). Another weak association (OR 2.63) was found between the C/T genotype of the −460C>T polymorphism and the occurrence of wet AMD. The occurrence of AMD was correlated with the presence of the combined C/T–G/G genotype of both polymorphisms (OR 2.41), whereas the T/T–G/G and T/T–G/C genotypes exerted a protective effect against the disease (OR 0.22 and 0.48, respectively). The presence of the C/T–G/G and C/T–C/C combined genotypes increased the risk of dry AMD (OR 2.08 and 3.77, respectively), whereas the presence of the T/T–G/G and T/T–G/C genotypes decreased the risk (OR 0.15 and 0.28, respectively). In the wet form of AMD, the combined genotype C/T–G/G slightly favored the disease (OR 2.61) and the T/T–G/G genotype had a protective effect (OR 0.25). Analysis of haplotypes of both polymorphisms yielded similar results for AMD in general as well as for the dry and wet forms of the disease: the CG haplotype favored both forms of AMD, whereas the TG haplotype protected against both forms of AMD. The results obtained indicate that the −460C>T and −634G>C polymorphisms of the VEGF gene may be associated with the dry and wet forms of AMD in a Polish population.  相似文献   
83.
Spliceosomal small nuclear ribonucleoproteins (snRNPs) in trypanosomes contain either the canonical heptameric Sm ring (U1, U5, spliced leader snRNPs), or variant Sm cores with snRNA-specific Sm subunits (U2, U4 snRNPs). Searching for specificity factors, we identified SMN and Gemin2 proteins that are highly divergent from known orthologs. SMN is splicing-essential in trypanosomes and nuclear-localized, suggesting that Sm core assembly in trypanosomes is nuclear. We demonstrate in vitro that SMN is sufficient to confer specificity of canonical Sm core assembly and to discriminate against binding to nonspecific RNA and to U2 and U4 snRNAs. SMN interacts transiently with the SmD3B subcomplex, contacting specifically SmB. SMN remains associated throughout the assembly of the Sm heteroheptamer and dissociates only when a functional Sm site is incorporated. These data establish a novel role of SMN, mediating snRNP specificity in Sm core assembly, and yield new biochemical insight into the mechanism of SMN activity.  相似文献   
84.
INTRODUCTION: Oxidative modification of proteins affects their biological properties. Previously we have shown that hypochlorite (HOCl), the product of activated neutrophils, enhances protein immunogenecity. Collagen type II, a primary component of cartilage, is commonly used in the induction of arthritis in animals (CIA). The aim of this study was to examine whether HOCl may affect immunogenic, tolerogenic, and arthritogenic properties of collagen. MATERIALS AND METHODS: DBA/J mice were injected with either native (CNAT) or chlorinated collagen (CHOCl) to induce arthritis. The effect of chlorination on collagen properties was measured by evaluation of incidence and severity of CIA. Moreover, the concentration of serum anti-collagen IgG antibodies and myeloperoxidase (MPO) activity in inflamed joints was determined. RESULTS: Mice immunized with CNAT in adjuvant developed arthritis (CIA) with an incidence of 69%. CNAT also exerted tolerogenic properties when injected intravenously either before or shortly after primary immunization, resulting in decreased incidence and severity of CIA, reduced MPO activity in inflamed joints, and lowered serum levels of anti-CNAT IgG anti-bodies. Chlorination of collagen significantly diminished its ability to induce CIA and to trigger generation of anti-CNAT IgG antibodies. Interestingly, chlorination did not affect tolerogenic properties of collagen administered prior to primary immunization with CNAT. CONCLUSIONS: These results suggest that chlorination of collagen may selectively affect functional epitopes of collagen. It is likely that in inflamed joints, neutrophil derived HOCl, in some circumstances, will destroy arthritogenic and immunogenic B cell epitopes, while regulatory T cell epitopes will be preserved.  相似文献   
85.
Tumor necrosis factor (TNF)-alpha plays a central role in the development of ophthalmopathy in patients with Graves' disease (GD). The aim of this study was to investigate the association of TNF promoter polymorphisms at positions -1031 (T-1031C), -863 (C-863A), -857 (C-857T), -308 (G-308A), and -238 (G-238A) with Graves' ophthalmopathy (GO). We studied the distribution of TNF and human leukocyte antigen (HLA) DRB1 alleles in 228 Polish white patients with GD, 106 of whom had ophthalmopathy (NOSPECS class > or = III) and 248 healthy subjects. TNF -308A and HLA-DRB1*03 alleles were significantly increased in patients with GD compared with healthy subjects. Stratification analysis revealed no independent association of -308A with GD when the DRB1*03 status was considered. Subdividing GD according to eye involvement revealed that the distribution of TNF promoter haplotypes differed significantly in patients with or without ophthalmopathy. The haplotype containing the -238A allele was absent in GO. The association of G-238A with GO was independent of DRB1 alleles. These results indicate that TNF G-308A is associated with susceptibility to GD (however, this association is not independent of HLA-DRB1*03) and that TNF G-238A is associated with the development of ophthalmopathy, suggesting that G-238A or a gene in linkage disequilibrium may be disease modifying in GD.  相似文献   
86.

Introduction

Mobile phone conversation decreases the ability to concentrate and impairs the attention necessary to perform complex activities, such as driving a car. Does the ringing sound of a mobile phone affect the driver''s ability to perform complex sensory-motor activities? We compared a subject''s reaction time while performing a test either with a mobile phone ringing or without.

Material and methods

The examination was performed on a PC-based reaction time self-constructed system Reactor. The study group consisted of 42 healthy students. The protocol included instruction, control without phone and a proper session with subject''s mobile phone ringing. The terms of the study were standardised.

Results

There were significant differences (p < 0.001) in reaction time in control (597 ms), mobile (633 ms) and instruction session (673 ms). The differences in female subpopulation were also significant (p < 0.01). Women revealed the longest reaction time in instruction session (707 ms), were significantly quicker in mobile (657 ms, p < 0.01) and in control session (612 ms, p < 0.001). In men, the significant difference was recorded only between instruction (622 ms) and control session (573 ms, p < 0.01). The other differences were not significant (p > 0.08). Men proofed to complete significantly quicker than women in instruction (p < 0.01) and in mobile session (p < 0.05). Differences amongst the genders in control session was not significant (p > 0.05).

Conclusions

The results obtained proofed the ringing of a phone exerts a significant influence on complex reaction time and quality of performed task.  相似文献   
87.
The ability to produce exopolysaccharides (EPS) is widespread among lactobacilli including Lactobacillus rhamnosus, the commonly used probiotic bacteria. Exopolysaccharides are a major component of the bacterial biofilm with a well‐documented impact on adherence of bacteria to host cells. However, their immunoregulatory properties are unknown. The aim of this study was to examine the immunostimulatory potential of EPS derived from L. rhamnosus KL37. We investigated the effect of EPS on the production of inflammatory mediators by mouse peritoneal macrophages and compared it with the effect of Lipopolysaccharide (LPS). Exopolysaccharides, at concentrations higher than those of LPS, stimulated production of both pro‐inflammatory (TNF‐α, IL‐6, IL‐12) and anti‐inflammatory (IL‐10) cytokines. Interestingly, analysis of the balance of TNF‐α/IL‐10 production showed a potential pro‐inflammatory effect of EPS. Furthermore, our data demonstrate that exposure of macrophages to LPS induced a state of hyporesponsiveness, as indicated by reduced production of TNF‐α after restimulation with either LPS or EPS (‘cross‐tolerance’). By contrast, EPS could make cells tolerant only to subsequent stimulation by the same stimulus. We also examined the relationship between TNF‐α production and activation of mitogen‐activated protein kinases (MAPKs) by EPS and LPS. Pretreatment of macrophages with specific inhibitors of p38 and ERK MAPKs reduced TNF‐α production induced by both stimuli to the same extent. In conclusion, these data demonstrate that EPS can effectively stimulate production of inflammatory mediators by macrophages in vitro. However, to predict whether EPS could be clinically useful as an immunomodulatory agent, further in vivo studies with highly purified EPS are necessary.  相似文献   
88.

Introduction

The aim of the study was to determine the correlation between pulsatile ocular blood flow (POBF) and sleep apnoea syndrome (SAS).

Material and methods

Patients were recruited from those who underwent polysomnography in the “Sleep Unit” of the physiology department (Medical University, Lodz, Poland). A total of 52 Caucasian patients, 34 with SAS and 18 age- and gender-matched controls, were included in the study. Comprehensive ophthalmic examination included the pulsatile ocular blood flow (POBF) measurements, disc analysis with Heidelberg Retina Tomograph II and Oculus Centerfield computerized perimetry as well as the best visual acuity, a slit lamp and indirect ophthalmoscopic evaluation of anterior and posterior segments and applanation tonometry.

Results

The observed prevalence of glaucoma in SAS patients was 5.9% (2 of 34). The mean values of POBF were 1069.21 ±235.94 µl/min in the SAS group and 1061.78 ±174.63 µl/min in the control group. The study revealed that the differences of mean POBF between the SAS patients and the control group were not statistically significant: Mann-Whitney U-test p > 0.05. No correlations were found between sleep apnoea syndrome and mean intraocular pressure (IOP), mean retinal nerve fibre layer (RNFL) thickness and visual field mean defect (MD).

Conclusions

No correlation was found between pulsatile ocular blood flow and sleep apnoea syndrome. Although some previous studies found an association between IOP, MD, RNFL thickness and sleep apnoea syndrome, our study did not confirm that. However, a high prevalence of glaucoma was found among SAS patients in Poland.  相似文献   
89.
Research within the anatomical sciences often relies on human cadaveric tissues. Without the good will of these donors who allow us to use their bodies to push forward our anatomical knowledge, most human anatomical research would come to a standstill. However, many research papers omit an acknowledgement to the donor cadavers or, as no current standardized versions exist, use language that is extremely varied. To remedy this problem, 20 editors‐in‐chiefs from 17 anatomical journals joined together to put together official recommendations that can be used by authors when acknowledging the donor cadavers used in their studies. The goal of these recommendations is to standardize the writing approach by which donors are acknowledged in anatomical studies that use human cadaveric tissues. Such sections in anatomical papers will not only rightfully thank those who made the donation but might also encourage, motivate, and inspire future individuals to make such gifts for the betterment of the anatomical sciences and patient care.  相似文献   
90.
This paper describes the cloning, sequencing and bacterial expression of the N protein of the Rift Valley fever virus (RVFV) ZIM688/78 isolate and its evaluation in indirect ELISAs (I-ELISA) for the detection of IgM and IgG antibodies in human and sheep sera. Sera used for the evaluation were from 106 laboratory workers immunised with an inactivated RVF vaccine, 16 RVF patients, 168 serial bleeds from 8 sheep experimentally infected with wild type RVFV and 210 serial bleeds from 10 sheep vaccinated with the live attenuated Smithburn RVFV strain. All human and animal sera that tested positive in the virus neutralisation test were also positive in the IgG I-ELISA. There was a high correlation (R2 = 0.8571) between virus neutralising titres and IgG I-ELISA readings in human vaccinees. In experimentally infected sheep IgG antibodies were detected from day 4 to 5 post-infection onwards and IgM antibodies from day 3 to 4. The IgG I-ELISA was more sensitive than virus neutralisation and haemagglutination-inhibition tests in detecting the early immune response in experimentally infected sheep. The I-ELISAs demonstrated that the IgG and IgM response to the Smithburn vaccine strain was slower and the levels of antibodies induced markedly lower than to wild type RVFV infection.  相似文献   
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