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41.
Phagocytes are a critical component of the innate immune response in humans and eliminate invading microorganisms through a process known as phagocytosis. Two distinct receptor-linked phagocytic pathways, one with Ab receptors (FcRs; FcR, Fc receptor) and the other complement receptors (CRs), mediate binding and ingestion of pathogens by human polymorphonuclear leukocytes (PMNs). Although progress has been made toward defining complex signal transduction processes that underlie phagocytosis in each pathway, very little is known about gene regulation during or after phagocytosis. Therefore, we used human oligonucleotide microarrays to identify changes in expression of 12,561 genes accompanying FcR- and CR-mediated phagocytosis. Eighty-four percent of 279 differentially expressed genes were induced or repressed 90 min after ingestion of Ab- and/or complement-opsonized particles. Unexpectedly, more than 30 of these genes encoded proteins involved in at least three distinct apoptotic pathways. Ninety-four differentially expressed cell fate-related genes were identified between 180 and 360 min after phagocytosis and most were induced or repressed by PMNs activated through both receptors simultaneously. By using flow cytometry, we found that FcR- and CR-mediated phagocytosis each promoted programmed cell death in human PMNs; however, phagocytosis mediated by the combination of FcRs and CRs induced apoptosis earlier than that by either receptor alone. Our results reveal distinct patterns of receptor-mediated gene expression that define complex inducible apoptotic pathways in activated PMNs. Most significantly, we discovered that programmed cell death is regulated at the level of gene expression. Thus, we hypothesize that gene regulation in PMNs facilitates resolution of inflammatory responses.  相似文献   
42.

Background

Bisphosphonate-related osteonecrosis of the jaws (BRONJ) is a complication of the bisphosphonate (BP) treatment and its pathopysiology is still not fully understood. The existing preventive and treatment options require updates and more attention. Geranylgeraniol (GGOH) so far demonstrated an increased activity and viability of the cells previously treated with zoledronic acid (ZA). The aim of this study was to evaluate the in vivo effects of GGOH on the development of BRONJ.

Materials and methods

A total of 30 male Wistar rats were included in the study, divided into three groups: two experimental groups (EG1 and EG2) and a control group (CG). Rats from EG1 and EG2 were treated with 0,06 mg/kg ZA ip weekly in a duration of five weeks, while CG received saline ip. On the third week all animals underwent extraction of the lower right first molars. The rats from EG2 received a local solution of GGOH in concentration of 5 mM in the socket every day after the tooth extraction. The analyses included clinical evaluation on the wound healing and pathohistological evaluation for presence and level of osteonecrosis.

Results

EG2 showed significantly improved wound healing and tissue proliferation, when compared to EG1. EG2 significantly differed from EG1 and CG (p<0,05) for the presence of microscopical osteonecrosis (80% vs 22,2% vs 0%). Regarding to the number of empty lacunes without osteocytes and the level of necrosis, all groups demonstrated significant differences.

Conclusion

Geranylgeraniol in a form of local solution may be a promising option for prevention and treatment of BRONJ.  相似文献   
43.
Newborn screening for severe primary immunodeficiencies (PID), characterized by T and/or B cell lymphopenia, was carried out in a pilot program in the Stockholm County, Sweden, over a 2-year period, encompassing 58,834 children. T cell receptor excision circles (TREC) and kappa-deleting recombination excision circles (KREC) were measured simultaneously using a quantitative PCR-based method on DNA extracted from dried blood spots (DBS), with beta-actin serving as a quality control for DNA quantity. Diagnostic cutoff levels enabling identification of newborns with milder and reversible T and/or B cell lymphopenia were also evaluated. Sixty-four children were recalled for follow-up due to low TREC and/or KREC levels, and three patients with immunodeficiency (Artemis-SCID, ATM, and an as yet unclassified T cell lymphopenia/hypogammaglobulinemia) were identified. Of the positive samples, 24 were associated with prematurity. Thirteen children born to mothers treated with immunosuppressive agents during pregnancy (azathioprine (n?=?9), mercaptopurine (n?=?1), azathioprine and tacrolimus (n?=?3)) showed low KREC levels at birth, which spontaneously normalized. Twenty-nine newborns had no apparent cause identified for their abnormal results, but normalized with time. Children with trisomy 21 (n?=?43) showed a lower median number of both TREC (104 vs. 174 copies/μL blood) and KREC (45 vs. 100 copies/3.2 mm blood spot), but only one, born prematurely, fell below the cutoff level. Two children diagnosed with DiGeorge syndrome were found to have low TREC levels, but these were still above the cutoff level. This is the first large-scale screening study with a simultaneous detection of both TREC and KREC, allowing identification of newborns with both T and B cell defects.  相似文献   
44.

Objective

To assess the erosive potential of various soft drinks by measuring initial pH and titratable acidity (TA) and to evaluate enamel surface roughness using different exposure times.

Materials and Methods

The initial pH of the soft drinks (group 1: Coca-Cola; group 2: orange juice; group 3: Cedevita; group 4: Guarana, and group 5: strawberry yoghurt) was measured using a pH meter, and TA was measured by titration with NaOH. Enamel samples (n = 96), cut from unerupted human third molars, were randomly assigned to 6 groups: experimental (groups 1–5) and control (filtered saliva). The samples were exposed to 50 ml of soft drinks for 15, 30 and 60 min, 3 times daily, during 10 days. Between immersions, the samples were kept in filtered saliva. Enamel surface roughness was measured by diamond stylus profilometer using the following roughness parameters: Ra, Rq, Rz, and Ry. Data were analyzed by one-way ANOVA, Tukey''s post hoc and Student-Newman-Keuls post hoc tests.

Results

The pH values of the soft drinks ranged from 2.52 (Guarana) to 4.21 (strawberry yoghurt). Orange juice had the highest TA, requiring 5.70 ml of NaOH to reach pH 7.0, whereas Coca-Cola required only 1.87 ml. Roughness parameters indicated that Coca-Cola had the strongest erosion potential during the 15 min of exposure, while Coca-Cola and orange juice were similar during 30- and 60-min exposures. There were no significant differences related to all exposure times between Guarana and Cedevita. Strawberry yoghurt did not erode the enamel surface regardless of the exposure time.

Conclusion

All of the tested soft drinks except yoghurt were erosive. Erosion of the enamel surfaces exposed to Coca-Cola, orange juice, Cedevita, and Guarana was directly proportional to the exposure time.Key Words: Soft drinks, pH, Titratable acidity, Dental enamel, Surface roughness, Stylus profilometry  相似文献   
45.
Detailed information regarding the neuroanatomy of reciprocal cerebrocerebellar pathways is based on well‐documented animal models. This knowledge has not yet been fully translated to humans, in that the structure of reciprocal cerebrocerebellar pathways connecting the cerebellum with frontal lobe has not been shown in its entirety. We investigated the impact of injury and age on cerebrocerebellar pathway microstructure using diffusion tensor imaging (DTI) and probabilistic tractography. We used medulloblastoma (MB) as an injury model due to the known impact of tumor/treatment on the cerebellum, one of the main nodes of cerebrocerebellar pathways. We delineated and segmented reciprocal cerebrocerebellar pathways connecting the cerebellum with frontal lobe in 38 healthy children (HC) and 34 children treated for MB, and compared pathway segment DTI measures between HC and MB and across three age cohorts: childhood, early adolescence, and late adolescence. Pathway compromise was evident for the MB group compared to HC, particularly within posterior segments (Ps<0.01). Though we found no age effect, group differences in microstructure were driven by pathway segment (posterior) and age cohort (adolescence), which may reflect the extent of injury to the posterior fossa following treatment for MB and age cohort differences in radiation treatment protocol in our sample. We have examined the microstructure of reciprocal cerebrocerebellar connections in the pediatric brain and have found that these pathways are injured in MB, a clinical population treated with surgery, radiation, and chemotherapy. Our findings support the late effects literature describing white matter injury emergence in the years following treatment for MB. Hum Brain Mapp 36:2615–2628, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
46.

Background

There is a lack of existing literature regarding the quality of esophagogastroduodenoscopy (EGD) reporting for gastric cancer evaluation. This study aims to determine criteria for quality endoscopic evaluation of gastric cancer in North America by identifying important features of the EGD report for pre-operative evaluation of gastric cancer and assessing inclusion of these features in existing reports.

Methods

Semi-structured interviews were conducted with experienced endoscopists from community and academic hospitals affiliated with the University of Toronto to identify essential elements for an EGD report. Then, 225 EGD reports from 2005 to 2008 were evaluated by two trained reviewers for inclusion of recommended EGD report elements and global assessment of report quality and adequacy for surgical planning.

Results

Essential elements recommended by interviewed endoscopists include tumor size, location, and distance from gastroesophageal junction (GEJ). Approximately 95 % of all reports documented the location of lesions, <5 % documented distance from the GEJ, and <15 % documented tumor size. Overall report quality was rated as excellent for 4–5 % of reports; 20–42 % of all reports were deemed to be adequate for surgical planning. All surgeons interviewed as part of the endoscopist panel indicated that they would repeat the EGD before consulting with patients regarding surgical planning.

Conclusions

For pre-operative evaluation of gastric cancer, tumor size, location, and distance from key anatomical landmarks were proposed as essential elements of a quality EGD report. Most of the reviewed reports did not document these elements. Report quality is perceived to be poor and may lead to repeat endoscopy. Developing a standardized EGD reporting format based on inclusion of individual parameters can improve the quality of gastric cancer management.  相似文献   
47.
The changes of free rotation around the carbon-carbon bonds in statistical chains of poly(styrene-co-dimethylitaconate) samples of different average composition were evaluated in terms of the σ-parameter, the ratio of the end-to-end distance of the coil in the unperturbed state to the same distance in a freely rotating chain. Samples of copolymers were carefully fractionated and fractions of identical composition selected for viscosity and light scattering measurements were subjected to the KURATA -STOCKMAYER extrapolation procedure, and KΘ and σ evaluated in terms of composition. Always between values of 2.17 and 2.02 for the parent homopolymers, σ goes through a slight minimum at about 33 mole-% of styrene. The phenomenon seems to stress the significance of electrostatic forces between opposite and neighbouring substituents of the poly(dimethylitaconate) chain which are comparable to the mutual incompatibility of unlike monomer residues in the copolymer chain.  相似文献   
48.
To assess health risks in agricultural workers associated with environmental exposure to pollutants released from a petroleum refinery and from traffic, we performed a cross-sectional study that included 119 randomly selected subjects divided in two groups. Group 1 included 60 agricultural workers living in a rural community near the petroleum refinery and a motorway overpass, whereas Group 2 consisted of 59 agricultural workers performing similar activities and living in a rural community with no exposure to industrial and traffic pollutants. Risk assessment included a questionnaire, blood pressure measurement, spirometry, laboratory tests, and toxicological analysis. The groups showed a similar prevalence of health problems, with exception of muscle pain in the extremities, headache, and fatigue, which were significantly more common in Group 1. Diastolic blood pressure was higher in Group 1, but not significantly (p=0.057). The same is true for blood carbon monoxide. Significantly higher in Group 1 were blood haemoglobin (p=0.001) and blood lead (p<0.001). Serum cholinesterase activity was similar in both groups. Our findings indicate the need of regular medical exams, ambient monitoring and environmental impact assessment in agricultural population in order to detect individuals at risk and to institute adequate preventive measures.  相似文献   
49.
Streptococcus pyogenes is an important human pathogen with an expansive repertoire of verified and putative virulence factors. Here we demonstrate that a mutant deficient in the production of the streptococcal ADP-ribosyltransferase SpyA generates lesions of reduced size in a subcutaneous mouse infection model. At early stages of infection, when the difference in lesion size is first established, inflamed tissue isolated from lesions of mice infected with spyA mutant bacteria has higher levels of mRNA encoding the chemokines CXCL1 and CCL2 than does tissue isolated from mice infected with wild-type bacteria. In addition, at these early times, the mRNA levels for the gene encoding the intermediate filament vimentin are higher in the mutant-infected tissue. As wound resolution progresses, mRNA levels of the gene encoding matrix metallopeptidase 2 are lower in mutant-infected tissue. Furthermore, we demonstrate that the spyA mutant is internalized more efficiently than wild-type bacteria by HeLa cells. We conclude that SpyA contributes to streptococcal pathogenesis in the mouse subcutaneous infection model. Our observations suggest that the presence of SpyA delays wound healing in this model.  相似文献   
50.
The primary objective of population-based newborn screening is the early identification of asymptomatic infants with a range of severe diseases, for which effective treatment is available and where early diagnosis and intervention prevent serious sequelae. Primary immunodeficiency diseases (PID) are a heterogeneous group of inborn errors of immunity. Severe combined immunodeficiency (SCID) is one form of PID which is uniformly fatal without early, definitive therapy, and outcomes are significantly improved if infants are diagnosed and treated within the first few months of life. Screening for SCID using T cell receptor excision circle (TREC) analysis has been introduced in many countries worldwide. The utility of additional screening with kappa recombining excision circles (KREC) has also been described, enabling identification of infants with severe forms of PID manifested by T and B cell lymphopenia. Here, we review the early origins of newborn screening and the evolution of screening methodologies. We discuss current strategies employed in newborn screening programs for PID, including TREC and TREC/KREC-based screening, and consider the potential future role of protein-based assays, targeted sequencing, and next generation sequencing (NGS) technologies, including whole genome sequencing (WGS).  相似文献   
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